settings.template.php

<?php
	/* ========================================================================================================
		$APP defines application specific settings:

		- title: string
			App title as displayed in header menu. If page_title is not set, this is also used as HTML <title> for the page
		- page_title: string (optional)
			What to put in the HTML title element. If not provided, the 'title' setting is used.
		- lang: DEPRECATED, DO NOT USE
		- bootstrap_css: string (optional) (default: bootstrap v3.3.6)
			Specify a bootstrap CSS theme, if you do not want to use the default theme.
		- page_icon: string (optional)
			Specify a path to an web page icon (aka 'favicon').
		- plugins: array (optional)
			Custom PHP files that will be included using require_once(). These plugins can contain functions that can be referenced anywhere in this file where external procedures can be provided (e.g. $LOGIN/initializer_proc). The index of the array can be any key that can be used to access the actual file name of the plugin from within the code.
		- cache_dir: string (optional, but recommended)
			Path to the directory where this app and its plugin can store their cache files. The path must not end with a trailing slash. The process that runs the php scripts on your machine must have read & write access to this directory. If this setting is undefined, there will be no caching.
		- page_size: int
			Pagination setting for MODE_LIST: max. number of items per page
		- pages_prevnext: int
			Pagination setting for MODE_LIST: max. number of pages to display left and right to the current one
		- max_text_len: int
			Max number of characters to display before text gets clipped in MODE_LIST
		- mainmenu_tables_autosort: bool
			Whether to sort the main menu entries alphabetically
		- view_display_null_fields: bool
			In MODE_VIEW, whether fields that have NULL value should be displayed (true) or omitted (false)
		- search_lookup_resolve: bool
			whether to lookup foreign key values instead of the FKs themselves
		- search_string_transformation: string (optional) (default: '%s')
			SQL expression used to define what transformation should happen both with the search query and the field before they are compared with each other. The placeholder for the argument is %s. This setting will typically be something like 'lower(%s)', or if languages with non latin characters are used 'unaccent(lower(%s))'.
		- null_label: string (default: 'NULL')
			label for the checkbox that allows explicit setting of a NULL value for a non-required field
		- render_main_page_proc: string (optional)
			called to render the main page after login.
			No parameters.
		- menu_complete_proc: string (optional)
			procedure called when default main menu has been built.
			function parameters: &$menu (assoc. array with complete menu for modification prior to rendering)
		- list_mincolwidth_max: int (optional) (default: 300)
			In MODE_LIST, column width is determined by cell content and set using CSS min-width. Specify here the maximum min-width that should be assigned
		- list_mincolwidth_pxperchar: int (optional) (default: 6)
			When determining min-width columns in MODE_LIST, how many pixels should be calculated for each character
		- custom_related_list_proc: string (optional)
			Name of a plugin function to call for extending the "List Related" dropdown in MODE_VIEW. This list of related records uses the search function to produce a list of records in a foreign table referencing the current one-
			Function parameters: $table_name (name of the current table), const &$table (table info - not to be modified), const &$pk_vals (hash with primary key values of currently viewed record), &$rel_list (current array of related list links).
			$rel_list can be extended with hash arrays containing values for the following keys: table_name (name of the related table), field_name (name of the field to search in the related table), display_label (item label to display in the dropdown menu)
		- preprocess_html_func: string (optional)
			Name of a function in a plugin to preprocesses any HTML output before it is written to the output buffer.
			Argument: $html (string with current text), Return: preprocessed string
		- additional_callable_plugin_functions: array (optional)
			List of function names that are allowed to be called via MODE_PLUGIN.
		- querypage_stored_queries_table: string (optional)
			If this is set, users are allowed to store and share queries via the database in MODE_QUERY. This setting controls the name of the table that will be created for this purpose in the database. If this is not set, users will not be able to store/share queries.
		- querypage_permissions_func: string (optional)
			Name of a function that returns a boolean value indicating whether the current user is allowed to interact with the page
		- register_custom_chart_type_func : string (optional)
			Name of a function that is called when the app asks for custom query visualizations. Typically this function will be in a plugin. In this function the app should call the QueryPage::register_custom_chart_type() with three parameters:
			* string $handle: used for 2 purposes: filename must be chart.$handle.php and class name must be dbWebGenChart_$handle
			* string $label: to be displayed in the dropdown box in the query editor
			* string $directory (optional, default = ''): location of the file relative to the app directory
		- querypage_show_visualization_settings: bool (optional) (default: true)
			Defines whether visualization settings box is shown on the query page.
		- querypage_table_simple_number_format: bool (optional) (default: false)
			Defines simple '#.#' format pattern for numeric tables in Google table visualizations. By default Google displays e.g. commas as grouping symbol which is not suitable for years. More fine tuning of data table formats can be achieved with the 'querypage_datatable_postproc_func' setting
		- querypage_datatable_postproc_func: string (optional)
			If set, specifies a javascript function to invoke after the data table for Google charts are populated. The function receives the DataTable instance as the only argument. Can be used, e.g., to adapt display formats for numbers, dates, etc.
		- lookup_allow_edit_default: boolean (optional) (default: false)
			Determines the default value for the setting field/lookup/allow_edit for CARDINALITY_MULTIPLE lookup fields.
		- preprocess_func: string (optional)
			Name of a function that will be called brefore any processing is performed by dbWebGen. Check engine.php about available includes
		- global_search: array (optional)
			If this assoc. array is provided, global full text search in all tables is enabled. Settings indicated with an asterisk (*) can be overriden in table and even field settings by providing a custom global_search setting array there.
			- include_table: boolean
				Whether or not to include each table by default in the global search. If this is set to false, global search will only work if this is overriden with global_search/include_table = true in at least one table.
			- min_search_len: int (optional) (default: 3)
				Minimum number of characters in the search string
			- max_preview_results_per_table: int (optional) (default: 10)
				Number of results to display in the overall preview.
			- max_detail_results: int (optional) (default: 100)
				Maximum number of results to display in detailed table view
			- search_string_transformation: string (optional) (default: $APP/search_string_transformation)
				Possibility to override the $APP/search_string_transformation setting if needed here
			- transliterator_rules: string (optional) (default: ':: Any-Latin; :: Latin-ASCII;')
				Rules to be used for PHP's Transliterator::createFromRules factory method.
			- cache_ttl: int (optional) (default: 3600)
				Number of seconds to cache each search result. Default is one hour. Note that this setting is only effective if $APP/cache_dir is set and valid. If you set this to 0, there will be no caching of global search results.
		- super_users: array (optional)
			You may provide an array of user names here, who will be allowed to configure the dbWebGen settings using the settings wizard
		- custom_query_data_provider: string (optional)
			In the query builder it is possible to reference a custom data provider instead of executing an SQL query, e.g. "{mydata}". When executing the query, the result data table is then fetched from the function referenced by this setting.
			The function receives two arguments:
				- $key: the key defined in the query string, in the example above: "mydata"
				- $params: a key/value array with parameters and their values, if the query is parameterized
			The engine expects this function to return an instance of PDOStatement. If this is not possible, e.g. when the resulting data is not coming from a PDO query, then the function may also return an instance of class PDOStatementEmulator (defined in /inc/db.php), which basically allows to create synthetic query results.
		- is_table_relevant_for_merge_func: string (optional)
			The name of a function to call when preparing the merging of records. The function returns a boolean defining whether the $referenced_table is relevant when determining referenced records from the $merge_table .
			Arguments:
				$merge_table: the current table on which the merge operation shall be performed
				$referenced_table: the table with referenced records
		- custom_menu: string (optional)
			Name of a function that is called to build the app's menu bar. Must return a hash array representing the menu.
			Example: 
			[
				[
					'name' => 'First dropdown',
					'items' => [
						[ 'label' => 'Some menu item', 'href' => '/some/path?param=valueX' ],
						[ 'label' => 'Another menu item', 'href' => '/some/path?param=valueY' ]
					]
				], [
					'name' => 'Second dropdown',
					'items' => [
						[ 'label' => 'Blah', 'href' => '/some/path?param=value1' ],
						[ 'label' => 'Lalalala', 'href' => '/some/path?param=value2' ]
					]
				]
			]
		- popup_hide_reverse_linkage: boolean (optional, default: false)
			If a "create new" button is clicked from a lookup field, then the popup might contain a dropdown that allows linkage via the same linkage table from which the popup was created. Setting this to true will hide those reverse associations in popups.
		- default_map_picker_options: array (optional)
			Default options to be used for leaflet map picker. Will be overwritten by any map picker options specified in any specific table field of type T_POSTGIS_GEOM

	======================================================================================================== */
	$APP = array(
		'plugins' => array(),
		'title' => '',
		'view_display_null_fields' => false,
		'page_size'	=> 10,
		'max_text_len' => 250,
		'pages_prevnext' => 2,
		'mainmenu_tables_autosort' => true,
		'search_lookup_resolve' => true,
		'search_string_transformation' => 'lower((%s)::text)',
		'null_label' => "<span class='nowrap' title='If you check this box, no value will be stored for this field. This may reflect missing, unknown, unspecified or inapplicable information. Note that no value (missing information) is different to providing an empty value: an empty value is a value.'>No Value</span>"
	);

	/* ========================================================================================================
		$DB has database connection details

		- type: { DB_POSTGRESQL, DB_MYSQL, DB_SQLITE }
			Database type. PostgreSQL and MySQL are supported.
			SQLite support is experimental and currently only intended for opening a database file and querying the database. Browsing and editing records will NOT work as expected.
		- host: string
			Database server (IP or hostname)
		- port: int
			Post number
		- user: string
			User name
		- pass: string
			Password
		- db: string
			Database to connect to. Note: currently only works with tables in the default schema.
			TODO: extend to allow for support of multiple schemas
	======================================================================================================== */
	$DB = array(
		'type' => DB_POSTGRESQL,
		'host' => 'localhost',
		'port' => 5432,
		'user' => 'XXX',
		'pass' => 'XXX',
		'db'   => 'XXX'
	);

	/* ========================================================================================================
		$LOGIN defines how authentication is done.

		If this array is empty, everyone can do everything.

		Login works with user records found in a database table or with any provided associative array.
		In any case, fields are required for primary_key, username_field, password_field, name_field
		and 'form' settings.

		- users_table: string | array
			If a string is provided, it must reflect the name of the table in the DB that contains the user records.
			If an array is provided, it must contain a list of associative arrays representing the user records.
		- primary_key: string
			Name of field in users_table that has the primary key, which identifies the record
		- username_field: string
			Name of the username field in users_table. Usernames must be unique.
		- password_field: string
			Name of the password field in users_table
		- name_field: string
			Name of the field containing the user's name in users_table
		- password_hash_func: string (optional)
			Name of the function to be used for password hashing, e.g. 'md5', 'sha1', etc.
			Works only with functions that take a single mandatory argument (the password)
		- password_verify_func: string (optional)
			Name of the function that compares the hash value with the plain text password.
			If not set, this will simply compare for equality of hash values.
			If a function is provided here, it needs to return true (password correct) or false (password incorrect). Signature:
				bool password_verify_func($plain, $hash);
		- form: array
			Field labels to display to the user in the login form
			- username: string
			- password: string
		- login_success_proc: string (optional)
			Called after successful login.
			No arguments.
		- initializer_proc: string (optional)
			Name of a function called at the very beginnging of processing. The function is called only when there is a logged in user.
			No arguments. NOTE: in some cases this function is NOT allowed to write anything to the output buffer!
		- allow_change_password: bool (optional) (default: true)
			Whether or not to allow each user to change their password. This is only applicable if the users are stored in the database, otherwise this setting is ignored.
		- guest_user: string (optional)
			Allows specifying a guest user account, which needs to have an empty password. If this setting is provided, the login form will have a button to log in as the guest user.
	======================================================================================================== */
	$LOGIN = array(
		'users_table' => 'users',
		'primary_key' => 'id',
		'username_field' => 'login',
		'password_field' => 'password',
		'name_field' => 'name',
		'password_hash_func' => 'md5',
		'allow_change_password' => true,
		'form' => array('username' => 'Username', 'password' => 'Password'),
	);

	/* ========================================================================================================
		$TABLES defines settings for all tables in the DB that play a role in the app

		Field names and table names MUST NOT be escaped in this settings file except in the 'sort' field setting.
		Each key reflects a table in the DB. The value is an array containing the following settings:

		- actions: array
			List of MODE_* actions that are allowed for the table (see config/constants.php)
		- hide_from_menu: array (optional)
			If set, the array shall include the MODE_* that identify the menu from which this table shall be hidden even if the action is allowed. Currently only menus for MODE_NEW and MODE_LIST are generated automatically, so these may be in the array.
		- display_name: string
			Text label for the table
		- description: string
			Text to display below the table heading in MODE_*
		- item_name: string
			Label for items stored in the table
		- primary_key: array
			- auto: bool
				Whether or not the key for this table is set automatically or entered manually.
				If auto = true, the primary key should consist of only one column (not sure about consequences otherwise!).
				If multiple columns, auto should be set to false (not sure about consequences otherwise!)
			- columns: array
				List of primary key fields. also if there is only one PK field, this needs to be an array
			- sequence_name: string (required only if auto=true)
				if auto = true, this becomes required and must reflect the sequence name that generates the new primary key value.
				If auto=false, this setting is ignored.
		- sort_lookup_raw: bool (default: false)
			Whether to perform an ORDER BY in list view based on the resolved display expressions of CARDINALITY_SINGLE lookups or based on their raw foreign key values. Setting this to true will speed up the sorting of very large tables by single lookup fields.
		- field_order: array (optional)
			Override the order in 'fields', which controls the order of fields in all views. The array here must include keys in 'fields' in the desired order. If only a subset of those keys are present in field_order, then those will determine the initial order of keys in 'fields', while the rest will remain unchanged.
		- fields: array
			Associative array with settings for each field. The key reflects the column name in the DB. The value is an array with several settings:
			- label: string
				Display label for this field, e.g. used as table head in MODE_LIST or form field label in MODE_NEW, etc.
			- type: any T_* defined in config/constants.php
				Type of the field.
				If type=T_LOOKUP: this is a pseudo type that reflects foreign keys from either 1:n (CARDINALITY_SINGLE) or m:n relationships (CARDINALITY_MULTIPLE). Settings for 'lookup' must be provided if this type is assigned (see below).
				If type=T_ENUM, 'values' must be set (see below)
			- len: int
				Maximal number of characters that the input control can hold. Relevant only for T_TEXT_LINE, T_TEXT_AREA, and T_PASSWORD.
			- display_remaining_chars: bool (default: false)
				If the text box has a character limit (see len setting above), the remaining character count will be displayed once the user focuses on the control.
			- required: bool (default: false)
				Whether or not a value is required for this field (= NOT NULL)
			- editable: bool (default: true)
				Whether or not this field should be offered in the new/edit forms. For an automatically generated primary key field or some computed field, this should be set to false. Even with editable=false, the field will be displayed in MODE_LIST and MODE_VIEW. If it is desired to completely hide this field from the user, the field itself should not be set in the fields array.
			- width_columns: int (optional) (default: calculated automatically for T_TEXT_LINE, otherwise 7)
				Specifies the number of columns in the bootstrap grid occupied by the input control.
			- height_rows: int (optional) (default: 5)
				Specifies the number of rows to be offered by the input control. Only applicable with T_TEXT_AREA.
			- resizeable: boolean (optional) (default: true)
				Controls whether a control is vertically resizeable. Only applies to T_TEXT_AREA.
			- help: string (optional)
				Help text to display in the new/edit forms. Can contain HTML.
			- show_setnull: bool (default: false)
				Whether or not to show a checkbox allowing to explicitly set a NULL value for a non-required field (applies to input and textarea). Even if the checkbox is not shown, it is there and automatically checked/unchecked upon user input.
			- default: string (optional)
				Default value to set. All occurrences of REPLACE_DYNAMIC_* strings (see config/constants.php) are replaced with the current values.
				For a T_BOOLEAN field, this must be either 'on' (=true) or 'off' (=false).
			- options: array (optional)
				Currently this is only relevant for T_BOOLEAN fields. This array is converted to a JSON object to initizalize the on/off toggle. All initialization options listed under http://www.bootstraptoggle.com/ can be provided. You should at least set the labels for 'on' and 'off' status of the toggle according to the purpose of this boolean field. If no options are provided here, the default labels for 'on' and 'off' states of the toggle are based on the localized strings boolean-field.default.yes and boolean-field.default.no, respectively.
			- values: array (required only if type=T_ENUM or T_BOOLEAN)
				For a T_ENUM type: An associative array with key reflecting the actual DB value, and value representing the label to display to the user, e.g. array(1 => 'January', 2 => 'February', ...)
				For a T_BOOLEAN type: This can be used to map 'on' and 'off' to other values than TRUE and FALSE, respectively; if provided, this must be an associative array with keys 'on' and 'off', e.g. array('on' => 'New Car', 'off' => 'Used Car'). Note that the values are sent to the DB, so they need to match the type of the column in the DB (in the example the target field could be a text column). It is recommended to provide custom values only for non-boolean columns.
			- allow_create: boolean (default: true)
				If set to false, suppresses the "Create New" button that is displayed next to T_LOOKUP boxes. Note: this setting might conflict with lookup/hide_dropdown setting
			- lookup: array	(required only if type=T_LOOKUP)
				Details of the foreign key relationship with another table
				- cardinality: {CARDINALITY_SINGLE, CARDINALITY_MULTIPLE}
					Whether this field is a foreign key in this very table (CARDINALTY_SINGLE), reflecting an 1:n relationship, or whether this relationship is actually represented in a separate table reflecting an m:n relationship (CARDINALITY_MULTIPLE). In the latter case, 'linkage' settings must be provided (see below)
				- table: string
					Name of the table referenced by this foreign key field
				- field: string
					Field in the table referenced by this foreign key field (typically the primary key of the other table)
				- display: (string|array)
					This setting is required to define what to display to the user. 
					This can be any of the following:
					* Field name: A string representing a field name in the referenced table
					    Example: 'display' => 'lastname'
					* Placeholder string: A string composed of string literals and field placeholders in curly brackets
					    Example: 'display' => '{lastname}, {firstname}'
					    This will concatenate the field value of lastname with ', ' and field value of firstname. Note: concatenation is done with || operator in SQL, so any NULL part will nullify the whole expression.
					    It is possible to display the value of a field from a table referenced from the lookup table using the following placeholder format: 
					      {field:fk_table:fk_other:fk_self}
						  field is the name of the field in the referenced table fk_table. The record is identified by linking via the foreign key fk_self (in the lookup table) to fk_other in the referenced fk_table.
					    Example: assuming these two tables:
						  city (city_id, name, state)
						  states (state_id, name)
						  where city.state is a foreign key reference to states.state_id						
						  Suppose we want to display the city in the format "city name, state name", then this would be our 'display' for fields that link to cities:
						  'display' => '{name}, {name:states:state_id:state}'
					* List of placeholder string: A flat array of placeholder strings. The array parts are concatenated using SQL function CONCAT(), which can include NULL parts without nullifying the whole expression
					    Example: 'display' => ['{lastname}, {firstname}', ' ({birthdate})']
						The equivalent SQL term would be something like: 
							CONCAT(lastname || ', ' || firstname, ' (' || birthdate || ')')					    
						Asuming lastname and firstname are always not null and birthday might be null, this will produce a name in "Lastname, Firstname" format and, if birthdate is not null, will append the birthdate in parentheses.
					* SQL expression: a hash array with 'columns' => array of columns, which is used in 'expression' => expression referring to indexes in 'columns' as %1, %2, etc.
					    Example: 
					      'display' => [
						    'columns' => ['firstname', 'lastname', 'birthdate'], 
						    'expression' => "concat_ws('', (%2 || ', ' || %1)", (' (' || %3 || ')'))"
						  ]
					    This will produce the exact same result as the placeholder string above:
					  	  'display' => ['{lastname}, {firstname}', ' ({birthdate})']
					    In fact, placeholder strings are translated into a column/expression hash array
				- sort: boolean (optional) (default: true)
					In case of multiple lookup values, this setting determines whether the linked records are sorted using the display expression. Only relevant for CARDINALITY_MULTIPLE.
				- dropdown_sort: string|array (optional) (default: asc)
					If a string is provided then 'desc' will sort the dropdown box in descending order, everything else will sort ascending (i.e. the default).
					If an array is provided, it needs to map fields to sort order, e.g.
						'dropdown_sort' => ['nr' => 'asc', 'label' => 'asc']
					Note: for CARDINALITY_MULTIPLE lookups, this may lead to unexpected behavior when a linked record is removed from list of linked records. The JS code that does the insertion is not aware of any database fields that are not displayed in the option's label. 
				- default: any type (optional)
					Default option for this foreign key reference to select in MODE_NEW. The type should be automatically convertible to string
				- related_label: string (optional)
					Text to display in the "List Related" dropdown in MODE_VIEW of any record of the table referenced by this field (e.g. "Cars Sold By This Agent")
					If missing, the label will be constructed automatically from the table's display name and the field's label. (e.g. "Cars Sales (As Agent)")
				- async: array (optional)
					Hash array that, when provided, specifies how to dynamically fetch records into the dropdown box based on keyboard input. This is handy if the linked table holds too many records. Keys:
					- min_input_len: integer
						Minimum number of characters the user has to type before matching records are fetched
					- delay: integer (optional) (default: 0)
						If set, this specifies the number of milliseconds to wait before sending an Ajax request after a user keystroke
					- max_results: integer (optional)
						If set, the number of results fetched from the async query is limited to this number. If the query would return more results, a notice is displayed to the user to make them aware of this fact
					- min_threshold: integer (optional)
					 	If set, the dropdown box will behave like a normal (non-async) control if less then the defined threshold number of options are available. Otherwise, if there are more options, or if this setting is not defined at all, the box will be an async lookup box.
				- label_display_expr_only: boolean (optional) (default: false)
					By default the label for lookup values is composed of the display expression and in parentheses the respective primary key name and value. If you wish to suppress the parentheses, set label_display_expr_only = true
				- hide_dropdown: boolean (optional) (default: false)
					In some cases it might be useful to allow only the creation of new associations using "Create New" button, and not through the dropdown box. If hide_dropdown is set to true, the dropdown box will not be shown. If the field is CARDINALITY_SINGLE and disabled for some reason, the dropdown will be shown regardless of the hide_dropdown setting. Note: this setting might conflict with the allow_create setting of the field. If hide_dropdown is set to true, allow_create must be set to true as well, otherwise nothing will be shown.
				- create_new_label: string (optional) (default: "Create New")
					Label for the button next to the dropdown box, which allows users to add new records to the linked table
				- allow_edit: boolean (optional) (default: see $APP/lookup_allow_edit_default)
					Whether to allow the user to edit the associated record from the lookup table. Note that setting this to true will only have an effect if the lookup table is configured in $TABLES, and MODE_EDIT is an allowed action there.
				- predefined_values: array (optional)
					Array mapping fieldnames (array keys) to their predefined values (array values), which will be used when the user creates a new record using the Create New button.
					Example:
					 	'predefined_values' => array(
							'name' => 'Barles Chronson',	// string value
							'height' => 1.78,				// numeric value
							'enemies' => '[3,77]'			// foreign keys for T_LOOKUP/CARDINALITY multiple field
							'mother' => array('field' => 'name') // field 'mother' will be preset with the current form's value of field 'name'
						)
				- field_settings_override: array (optional)
					Array mapping fieldnames (array keys) to settings that override those in settings.php or the current context. This array will be used when the user creates a new record using the Create New button. Use this with caution, since it may contractict the constraints in the DB or the dbWebGen logic.
					Each value is either
						h ... hide the control
					Or any combination of
						e ... enable the control
						d ... disable the control
						r ... make field required
						o ... make field optional
						s ... show the control if hidden
					Example:
					 	'field_settings_override' => array(
							'name' => 'h',		// hide field
							'height' => 'e',	// enable field (useful in conjunction with predefined_values)
						)
				- no_link: boolean (optional) (default: false)
					Suppress the rendering of a hyperlink to the linked item in MODE_VIEW and MODE_LIST.
				- link_to_lookup_record: boolean (optional) (default: false)
					If this is set to true, then the displayed hyperlink will point to the associated record instead of pointing to the record in the linkage table. This setting is only relevant for CARDINALITY_MULTIPLE fields where the linkage table is defined and its 'actions' setting allows MODE_VIEW. Otherwise the link will point to the associated record regardless of the 'link_to_lookup_record' setting. Also note that this setting has no effect if 'no_link' is set to true.
				- condition: array (optional)
					Allows specifying a condition on the lookup records. Only records that satisfy the condition are displayed in the dropdown.
					Must be a hash array with two keys:
						- columns: array of column names used in the expression
						- expression: string with conditional SQL expression; may refer to columns by using their 1-based index in the column array, e.g. %1, %2, so forth.
					Example: restrict lookup items to those where type is car and origin is US or EU: 
						'condition' => [
							'columns' => ['type', 'origin'],
							'expression' => "%1 = 'car' and %2 in ('US', 'EU')"
						]
			- linkage: array
				If cardinality=CARDINALITY_MULTIPLE, we need to define here the m:n relationship table that links records from this table (via fk_self) with records of the other table (via fk_other)
				- table: string
					Table name
				- fk_self: string
					Foreign key field referencing this table
				- fk_other: string
					Foreign key field referencing the other table
				- defaults: array (optional)
					Array of field defaults for non-key fields in the form FIELD_NAME => VALUE. For each field, occurrences of REPLACE_DYNAMIC_* strings (see config/constants.php) in VALUE are replaced with the current values.
				- render_func: string (optional)
					By default, multiple records are simple separated by MULTIPLE_RECORDS_SEPARATOR. By providing a custom function name here, you can change the default behavior for rendering the linkage to be applied in MODE_VIEW (in MODE_LIST this does not work because of potential clipping via $APP/max_text_len setting). The function signature:
						function render_func(&$field, $item_html, $index, $total_num_items, &$params)
						* &$field is the field settings array
						* $item_html is the HTML code for the linked item
						* $index is the item's index in the list
						* $total_num_items is the total number of items in the list
						* &$params is reserved for future use; currently the engine will pass a reference to an empty array
						The function must return the HTML to be rendered for the current item.
				- maxnum: int (optional) (default: 0)
					If a number greater than zero is provided here, the number of linked records will be limited to this number. When maxnum is reached, the dropdown and the create new button will be disabled. This setting is only considered if cardinality is CARDINALITY_MULTIPLE
			- SRID: int (required only for type=T_POSTGIS_GEOM)
				Spatial Reference ID of the Postgis geometry
			- min_len: int (optional)
				This setting is only ueful for type=T_PASSWORD. If it is set, users will have to provide a password of this minimum length
			- password_chars: array (optional)
				This setting defines requirements for types of characters that have to occur in passwords. The following keys can be defined:
				- lower: int (optional; default: 0)
					Required number of lower case characters (a-z)
				- upper: int (optional; default: 0)
					Required number of upper case characters (A-Z)
				- number: int (optional; default: 0)
					Required number of number characters (0-9)
				- other: array (optional)
					- chars: string
						String of allowed other characters
					- min: int
						Required number of other characters
			- max_size: int (optional)
				Only evaluated for type=T_UPLOAD, to limit the file size for uploads
			- location: string (required for type=T_UPLOAD && store=STORE_FOLDER)
				Only evaluated for type=T_UPLOAD, to specify the server side subfolder where to store uploaded files.
			- store: bitwise combination of {STORE_FOLDER, STORE_DB} (required for type=T_UPLOAD)
				Only evaluated for type=T_UPLOAD, to specify where the uploaded file shall be stored.
				If store & STORE_DB, then the file will be stored binary in this field (TODO: not implemented yet)
				If store & STORE_FOLDER, then the file will be stored in a folder specified by 'location'
			- allowed_ext: array (optional)
				If type=T_UPLOAD, the file extension of the uploaded file will be checked against this array
			- post_proc: string (optional)
				Name of a function that will be called after the file was uploaded to the server.
				Arguments: table name, field name, file info array, file path
			- filename_override: string (optional)
				For T_UPLOAD fields, this can be the name of a function to be called before storing the file to the final storage location. The function must return true if the filename was changed, and false if it was not changed
				Function parameters:
					* $table_name: Name of the current table
					* $field_name: Name of the file upload field
					* $cur_filename: Current file name (= file name on user's computer)
					* &$new_filename: Output parameter taking the new desired filename
			- reset: bool (default: false)
				reset=true means that when editing a record (MODE_EDIT) its current value is not fetched into the form control.
			- min: number (optional)
				for T_NUMBER, define the minimum value for the field
			- max: number (optional)
				for T_NUMBER, define the maximum value for the field
			- step: number or string (optional) (default: 1)
				for T_NUMBER, define the step size for up/down (e.g. 3 or 0.01). If not restricted, use 'any'
			- cell_css: string (optional) (default: none)
				any value will be set as the CSS style of the table cell in MODE_LIST
			- view_css: string (optional) (default: none)
				any value will be set as the CSS style of the display div in MODE_VIEW
			- number_format: array (optional)
				for T_NUMBER, a hash array with the following keys
					* template (string): a string specifying a combination of the following number components:
						a ... text to display after (specified by key 'after')
						b ... text to display before (specified by key 'before')
						c ... currency (specified by key 'currency')
						e ... non-breaking space
						m ... sign: - only
						n ... the actual number (formatted according to settings below)
						s ... sign: + or -
					* decimals (int): number of decimals
					* dec_point (string): decimal point character
					* thousands_sep (string): thousands separator character
					* currency (string): currency symbol (required only if "c" part of template)
					* before (string): text to display before (required only if "b" part of template)
					* after (string): text to display after (required only if "a" part of template)
					* strip_trailing_decimal_zeros (optional, default: false) (bool): if true, will strip any trailing zeros after the decimal point
				Note: if number_format is provided, the setting max_decimals is ignored
			- conditional_form_label: array (optional)
				In MODE_NEW & MODE_EDIT forms, this controls field labels based on the value of another field (currently the other field must be T_ENUM or T_LOOKUP).
				- controlled_by: string
					The field within the same table that controls the label
				- mapping: array
					Hash array with key := value of the other field, and value := corresponding label of this field.
					If the othe field has a value that is not represented in this mapping hash, the label will be the default field label
			- list_hide: boolean (optional) (default: false)
				Determines whether this field is hidden from the table in MODE_LIST
			- view_hide: boolean (optional) (default: false)
				Determines whether this field is hidden from the record display in MODE_VIEW
			- sort_expr: string (optional) (default: '%s')
				If a table is sorted in MODE_LIST, this expression defines how the field to sort is handled in the ORDER BY clause using sprintf(). The default '%s' expression results in a "normal" sorting using ORDER BY with simply the fieldname. Use this setting e.g. for custom sorting using functions. Example: 'naturalsort(%s)'
			- max_decimals: int|array (optional)
				Allows specifying the maximum number of digits to display for T_NUMBER fields (ignored for other field types)
				If an integer is provided, this will be the maximum number of digits (e.g. 'max_decimals' => 5 will limit to 5 decimal digits)
				If an array is provided, the array keys map the MODE_* to the maximum number of digits to show in this view (e.g. 'max_decimals' => array(MODE_VIEW => 5) will limit the display to 5 decimal digits only in MODE_VIEW)
				If this setting is not provided, any T_NUMBER value will be rendered after it has been cast to float
				Note: if number_format is provided, the setting max_decimals is ignored
			- tab: string (optional)
				If the form_tabs setting was provided for this table, refer the identifier of the tab to which this field belongs. In a tabbed form, if the field's tab identifier is missing, it is assumed that the field belongs to the first tab.
			- map_picker: array (optional)
				For T_POSTGIS_GEOM fields, if this array is set, the user will be able to pick a point from a map that appears in a popup window.
				Provide the following settings:
					- map_options: array (optional)
						An optional hash array that will be passed on as a Map_options object to the Leaflet L.Map constructor (see http://leafletjs.com/reference#map-options)
					- draw_options: array (optional)
						An optional hash array that will be passed on as a DrawOptions object to the Leaflet.Draw L.Control.Draw constructor (see https://leaflet.github.io/Leaflet.draw/docs/leaflet-draw-latest.html#drawoptions).
					- script: string|array (optional)
						Any javascript file (string) or files (array of strings) to include. Two javascript functions will be called form the map picker, if these functions exist:
						* map_picker_init_map() immediately after leaflet has occupied the map div
						* map_picker_finish_init() immediately after the map picker initialization is completed
						In the script, the following global variables will be available:
						* map (L.Map) - the Leaflet map
						* curPointLayer (L.Layer) - the Leaflet layer that contains the pre-existing point
						* drawnItems (L.FeatureGroup) - the feature group object that Leaflet.Draw uses to capture the user-drawn layers
			- placeholder: string (optional)
				Force a particular placeholder text to be displayed in the respective form control for MODE_NEW and MODE_EDIT. By default, no placeholders are displayed, except for T_ENUM and T_LOOKUP fields, which will display a hint to click the dropdown. Setting a placeholder is particularly useful when the form control is part of a group of fields (see setting field_groups).
			- field_groups: array (optional)
				Allows to define a number of field groups for the form. A field group has a label (like any normal field), but the field group can have multiple form controls. Each field group is defined by an array as follows:
					- label: string
						The label to display on the form, similar to the field/label setting
					- help: string (optional)
					 	The help popup text, similar to the field/help setting
					- label_tooltip: string (optional)
						Tooltip text to display when the mouse hovers over the field group label
					- fields: array
						An ordered hash array mapping the field name (each must be present in fields) to the number of columns which the field's form control shall occupy in the form. This value must be an integer between 1 and 12. One row in the form consists if 12 columns. When the 12 columns are exceeded, a new row will begin automatically.
				Example:
					'field_groups' => array(
						array(
							'label' => 'Birth date',
							'help' => 'Enter the person\'s birthday.',
							'label_tooltip' => 'Only the year is mandatory, but try to enter all date available components.'
							'fields' => array(
								'dob_year' => 6,
								'dob_month' => 3,
								'dob_day' => 3
							)
						)
					)
			- datetime_picker: array (optional)
				For T_TEXT_LINE fields, use this to attach a datetime picker to this field (useful e.g. for timestamp, time or date fields in the DB). The settings array can include any of the settings allowed by eonasdan's bootstrap-datetimepicker at initialization (http://eonasdan.github.io/bootstrap-datetimepicker/Options/). Note that the "showClear" setting will be autoamtically set based on whether the field is required or not; and the "defaultDate" setting only has an effect if the field has no value yet in the DB. Additional to the picker options you can add a setting "mainIcon" to this array, which will control the icon displayed in the input control; use any glyphicon class, by default "glyphicon glyphicon-calendar" will be used.
				Example:
					..., 'datetime_picker' => array(
						'format' => 'YYYY-MM-DD', // include time, e.g. HH:mm to also enable time picker
						'showTodayButton' => true
					), ...
			- conditional_display: array (optional)
				This array controls the visibility of this field in the new/edit forms based on the value of other fields. The array consists of conditional expressions, optionally separated by logical operators OPERATOR_AND or OPERATOR_OR
				Each conditional expression is a hash array that maps the following keys:
					- field: string
						The other form field whose value is relevant for the expression
					- operator: string
						The operator to compare the other field's value; see the OPERATOR_* defined in constants.php; all of them are possible to use here, except OPERATOR_AND, OPERATOR_OR, OPERATOR_GROUP_*; if any of OPERATOR_ARRAY_* is used, the referenced field must be type T_LOOKUP with CARDINALITY_MULTIPLE, otherwise errors may occur.
					- value: any
						The value will be used as right hand operand of the expression. Its type should match the other field's type. For OPERATOR_EQUALS and OPERATOR_NOT_EQUALS, an array can be given here, testing for set membership (OPERATOR_EQUALS) or non-set membership (OPERATOR_NOT_EQUALS)
					- control_filter: string (optional)
						Some UI libraries (e.g. bootstraptoggle for T_BOOLEAN) mask the original control; here you can specify an expression to be used as argument for the jQuery controls is() function when looking for the field's control, e.g. for T_BOOLEAN use 'control_filter' => 'input[type=checkbox]'
					- control_prop: string (optional)
						By default the control's value to check against is retrieved using jQuery's val() function. If instead you want to check for a property, specify the control's property to check against here, e.g. for T_BOOLEAN specify 'control_prop' => 'checked'
				Expressions can be grouped and nested using OPERATOR_GROUP_OPEN (corresponds to an opening parenthesis) and OPERATOR_GROUP_CLOSE (corresponds to closing parenthesis).
				Consider the following example:
					'conditional_display' => array(
						array('field' => 'name', 'operator' => OPERATOR_EQUALS, 'value' => array('Staatsoper', 'Empire State Building')),
						OPERATOR_OR,
						OPERATOR_GROUP_OPEN,
							array('field' => 'location_id', 'operator' => OPERATOR_NOT_EQUALS, 'value' => ''),
							OPERATOR_AND,
							array('field' => 'nr', 'operator' => OPERATOR_BETWEEN, 'value' => array(3, 7)),
						OPERATOR_GROUP_CLOSE
					)
					In this example, the field is displayed if the 'name' field either contains any of the values of "Staatsoper" or "Empire State Building", OR when both of the following conditions are met: field 'location_id' is not empty, and field 'nr' contains a number between 3 and 7.
			- richtext: array (optional)
				Turns a T_TEXT_AREA input into a rich text editor. The following options are possible:
					- editor: string
						Currently only 'trumbowyg' editor is supported. See https://alex-d.github.io/Trumbowyg
					- init_options: array (optional)
						If provided, this hash array will be converted to a JSON object and passed to the editor initialization function.
			- display_value_postproc: string (optional)
				Name of a function to call when displaying the value of a field in MODE_VIEW or MODE_LIST. The function must return the value to display.
				The function will receive the following arguments:
					* $html_value (string): HTML string that was generated by dbWebGen (i.e. the default value display behaviour)
					* $table_name (string): Name of the current table
					* $field_name (string): Name of the current field
					* $record (hash array): The current raw data record from the DB to be prepared for display
			- render_as_url: boolean (optional; default: false)
				If the field is T_TEXT_LINE and this setting is true, then the field content will be rendered as a Hyperlink.

		- sort: array (optional)
			Used for default sorting of tables in MODE_LIST. Associative array with key := fieldname (or SQL expression) and value := {'asc', 'desc'}
			e.g. [ 'lastname' => 'asc, 'firstname' => 'asc' ]
		- hooks: array (optional)
			Functions to call before/after certain events. Associative array with key reflecting the event, and value reflecting the function to call.
			Possible keys:
			- after_insert: string (optional), after_update: string (optional), after_delete: string (optional)
				Function to call after insertion/update/deletion of a record.
				Arguments: (1) table name (2) table settings and (3) primary key/value array.
				For hook after_delete_ex, an additional associative array with the deleted record is provided as argument
			- before_insert: string (optional), before_update: string (optional), before_delete: string (optional)
				Function to call before insertion/update/deletion of a record. Be careful with before_delete hook since the acutal deletion might fail
				Arguments: (1) table name (2) table settings (3) column names array reference, (4) column values array reference
		- additional_steps: array (optional)
			Steps offered to be performed after a new record was created to link this record with others via separate linkage tables. The key reflects the linked table, the value is an array with these values:
				- label: string
					Link label for this action
				- foreign_key: document
					Foreign key field that links to this table from the n:m table
			e.g. in table customers:
			'additional_steps' => array('orders' => array('label' => 'Orders of this customer', 'foreign_key' => 'customer_id'))
		- auto_append_additional_steps: boolean (optional) (default: false)
			If true, appends links to create related records with a predefined link to this one.
		- custom_actions: array (optional)
			Array of arrays, each representing a custom action that is offered in particular viewing modes through particular buttons. Each custom action is an associative array consisting at least of the following keys:
				- mode: string
					Any of the MODE_* modes to which this action applies (currently only MODE_LIST implemented)
				- handler: string
					Name of a handler function that will be called for the current record. Arguments: (1) name of the current table (2) table info from this settings file (3) the record retrieved from the database using PDO::FETCH_ASSOC and (4) this very custom action hash, which means that any additional key/value pairs you add to this array will get passed to the handler function.
		- show_in_related: bool (optional) (default: true)
			In MODE_VIEW, there is a dropdown linking to tables where the current record is linked through a foreign key (T_LOOKUP). If you do not want this table to appear in this list at all, set this to false.
		- render_links: array (optional)
			If MODE_LINK is allowed in this table, then there will be an extra icon in the table in MODE_LIST for each record that allows to view the actual object represented by the record. Also there will be an extra button in MODE_VIEW that features this link. An associative array has to be provided for each entry in this array (note that you must provide either href_callback or both href_format and field):
				- modes: array (optional; default: [MODE_LIST, MODE_VIEW])
					The display modes in which this link shall be displayed.
				- icon: string
					The name of a glyphicon that works with bootstrap, e.g. "eye-open" or "trash". See a list here: http://www.w3schools.com/bootstrap/bootstrap_ref_comp_glyphs.asp
				- title: string
					Title (tooltip) shown when hovering over the link icon in MODE_LIST
				- btn_label: string (optional)
					Label shown on button in MODE_VIEW
				- href_callback: string 
					Name of a function to be called for retrieving the hyperlink. The function will receive as arguments the current database record as an associative array, and the name of the current table. The function must either return a hyperlink or boolean false. In the latter case, no link will be displayed. 
				- href_format: string
					A URL template that will be used in a sprintf() call. Each %s must be matched by a field name in the 'fields' parameter:
				- field: string|array
					Name of the field (or array of field names) whose value(s) will be used to replace the %s placeholders in href_format
				- list_insert_position: string (optional; default: 'head')
					Where to insert the icon relative to the default icons in MODE_LIST ('head' or 'tail')
				- view_insert_position: string (optional; default: 'tail')
					Where to insert the icon relative to the default icons in MODE_VIEW ('head' or 'tail')
			Example: 
				'render_links' => array(
					array('icon' => 'eye-open', 'href_format' => 'uploads_images/%s', 'field' => 'filename', title => 'Show the damn file')
				)
			Example with array of fields:
				'render_links' => array(
					array('icon' => 'eye-open', 'href_format' => 'somedir/%s/id/%s', 'field' => ['filename', 'id'], title => 'Show the damn file')
				)
		- custom_buttons: array (optional)
			List of buttons to be displayed in MODE_LIST on top of the table. For each entry in this array a hash array with the folloing key/value pairs needs to be provided:
				- icon: string
					The name of a glyphicon that works with bootstrap, e.g. "eye-open" or "trash". See a list here: http://www.w3schools.com/bootstrap/bootstrap_ref_comp_glyphs.asp
				- label: string
					Button label
				- href: string 
					Hyperlink of the button
				- tooltip: string (optional)
					Tooltip shown when hovering over the button
			Example: 
				'custom_buttons' => [
					[ 'icon' => 'upload', 'href' => '?mode=plugin&func=plugin_csv_import&table=mytable', 'label' => 'Import CSV' ]
				]
		- form_tabs: array (optional)
			If a tabbed MODE_NEW / MODE_EDIT / MODE_VIEW form is desired, fill this array with the following settings:
				- tabs: array
					An ordered set of arrays, where each array reflects a tab. Settings:
					- id: string
						Identifier of the tab, to be used in the 'tab' setting of the table's fields.
					- label: string
						Label to display on the tab
					- intro: string (optional)
						If specified, any information (HTML encoded) that should be displayed at the top of the form tab.
				- restrict_modes: array (optional)
					If tabs are only desired in subset of {MODE_NEW, MODE_EDIT, MODE_VIEW}, specify this subset as an array here.
		- validation_func: string (optional)
			Allows naming a validation function that is invoked upon submission of the MODE_NEW/MODE_EDIT form. This function needs to be implemented in JavaScript; the file in which it is implemented needs to be included via the add_javascript() helper function; the best place to do this in most circumstances is the preprocess_func defined in $APP (see above).
			The function is called with three arguments:
				- table_name: string (the current table)
				- table_settings: object (a JS object representing the table's settings from settings.php)
				- values: object (for each column this object maps the column name to the value entered in the form)
			Expected return values:
				- If there are errors in the form, the function must a JSON object that maps each erroneous form field to an error message that shall be displayed next to the form field.
				- If there are no errors in the form, the function must return null

	======================================================================================================== */
	$TABLES = array(
	);
?>