support query

iotdb-client/client-py/TableModelSessionExample.py

@@ -0,0 +1,79 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# "License"); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+#
+
+from iotdb.Session import Session
+
+# creating session connection.
+ip = "127.0.0.1"
+port_ = "6667"
+username_ = "root"
+password_ = "root"
+
+# don't specify database in constructor
+session = Session(ip, port_, username_, password_, sql_dialect="table")
+session.open(False)
+session.execute_non_query_statement("CREATE DATABASE test1")
+session.execute_non_query_statement("CREATE DATABASE test2")
+session.execute_non_query_statement("use test2")
+
+# or use full qualified table name
+session.execute_non_query_statement(
+    "create table test1.table1(region_id STRING ID, plant_id STRING ID, device_id STRING ID, model STRING ATTRIBUTE, temperature FLOAT MEASUREMENT, humidity DOUBLE MEASUREMENT) with (TTL=3600000)"
+)
+session.execute_non_query_statement(
+    "create table table2(region_id STRING ID, plant_id STRING ID, color STRING ATTRIBUTE, temperature FLOAT MEASUREMENT, speed DOUBLE MEASUREMENT) with (TTL=6600000)"
+)
+
+# show tables from current database
+with session.execute_query_statement("SHOW TABLES") as session_data_set:
+    print(session_data_set.get_column_names())
+    while session_data_set.has_next():
+        print(session_data_set.next())
+
+# show tables by specifying another database
+# using SHOW tables FROM
+with session.execute_query_statement("SHOW TABLES FROM test1") as session_data_set:
+    print(session_data_set.get_column_names())
+    while session_data_set.has_next():
+        print(session_data_set.next())
+
+session.close()
+
+# specify database in constructor
+session = Session(
+    ip, port_, username_, password_, sql_dialect="table", database="test1"
+)
+session.open(False)
+
+# show tables from current database
+with session.execute_query_statement("SHOW TABLES") as session_data_set:
+    print(session_data_set.get_column_names())
+    while session_data_set.has_next():
+        print(session_data_set.next())
+
+# change database to test2
+session.execute_non_query_statement("use test2")
+
+# show tables by specifying another database
+# using SHOW tables FROM
+with session.execute_query_statement("SHOW TABLES") as session_data_set:
+    print(session_data_set.get_column_names())
+    while session_data_set.has_next():
+        print(session_data_set.next())
+
+session.close()

iotdb-client/client-py/iotdb/Session.py

@@ -73,6 +73,7 @@ class Session(object):
     DEFAULT_PASSWORD = "root"
     DEFAULT_ZONE_ID = time.strftime("%z")
     RETRY_NUM = 3
+    SQL_DIALECT = "tree"
 
     def __init__(
         self,
@@ -83,6 +84,8 @@ def __init__(
         fetch_size=DEFAULT_FETCH_SIZE,
         zone_id=DEFAULT_ZONE_ID,
         enable_redirection=True,
+        sql_dialect=SQL_DIALECT,
+        database=None,
     ):
         self.__host = host
         self.__port = port
@@ -103,6 +106,8 @@ def __init__(
         self.__enable_redirection = enable_redirection
         self.__device_id_to_endpoint = None
         self.__endpoint_to_connection = None
+        self.__sql_dialect = sql_dialect
+        self.__database = database
 
     @classmethod
     def init_from_node_urls(
@@ -180,12 +185,15 @@ def init_connection(self, endpoint):
         else:
             client = Client(TBinaryProtocol.TBinaryProtocolAccelerated(transport))
 
+        configuration = {"version": "V_1_0", "sql_dialect": self.__sql_dialect}
+        if self.__database is not None:
+            configuration["db"] = self.__database
         open_req = TSOpenSessionReq(
             client_protocol=self.protocol_version,
             username=self.__user,
             password=self.__password,
             zoneId=self.__zone_id,
-            configuration={"version": "V_1_0"},
+            configuration=configuration,
         )
 
         try:
@@ -1364,6 +1372,8 @@ def execute_non_query_statement(self, sql):
             else:
                 raise IoTDBConnectionException(self.connection_error_msg()) from None
 
+        if resp.database is not None:
+            self.__database = resp.database
         return Session.verify_success(resp.status)
 
     def execute_statement(self, sql: str, timeout=0):