diff --git a/CHANGELOG.md b/CHANGELOG.md
index 23afc87..d2b045e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,12 @@
 # Change Log
 
+## Version 1.15.2
+
+Released on June 13, 2021
+
+- Allow empty key names in JSON output. ([GitHub #57](https://github.com/mithrandie/csvq/issues/57))
+- Fix a bug of the "--allow-uneven-fields" option. ([GitHub #59](https://github.com/mithrandie/csvq/issues/59))
+
 ## Version 1.15.1
 
 Released on May 5, 2021
diff --git a/docs/changelog.md b/docs/changelog.md
index 03d99a3..6219d98 100644
--- a/docs/changelog.md
+++ b/docs/changelog.md
@@ -5,6 +5,13 @@ title: Change Log - csvq
 
 # Change Log
 
+## Version 1.15.2
+
+Released on June 13, 2021
+
+- Allow empty key names in JSON output. ([GitHub #57](https://github.com/mithrandie/csvq/issues/57))
+- Fix a bug of the "--allow-uneven-fields" option. ([GitHub #59](https://github.com/mithrandie/csvq/issues/59))
+
 ## Version 1.15.1
 
 Released on May 5, 2021
diff --git a/docs/index.md b/docs/index.md
index 9b60b01..0eb981e 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -13,10 +13,10 @@ In the multiple operations, you can use variables, cursors, temporary tables, an
 
 ## Latest Release
 
-Version 1.15.1
-: Released on May 5, 2021
+Version 1.15.2
+: Released on June 13, 2021
 
-  <a class="waves-effect waves-light btn" href="https://github.com/mithrandie/csvq/releases/tag/v1.15.1">
+  <a class="waves-effect waves-light btn" href="https://github.com/mithrandie/csvq/releases/tag/v1.15.2">
     <i class="material-icons left">file_download</i>download
   </a>
 
diff --git a/docs/sitemap.xml b/docs/sitemap.xml
index 051ebab..25af5ca 100644
--- a/docs/sitemap.xml
+++ b/docs/sitemap.xml
@@ -6,7 +6,7 @@
             http://www.sitemaps.org/schemas/sitemap/0.9/sitemap.xsd">
     <url>
         <loc>https://mithrandie.github.io/csvq/</loc>
-        <lastmod>2021-05-05T00:06:28+00:00</lastmod>
+        <lastmod>2021-06-13T14:02:24+00:00</lastmod>
     </url>
     <url>
         <loc>https://mithrandie.github.io/csvq/reference.html</loc>
@@ -178,7 +178,7 @@
     </url>
     <url>
         <loc>https://mithrandie.github.io/csvq/changelog.html</loc>
-        <lastmod>2021-05-05T00:06:28+00:00</lastmod>
+        <lastmod>2021-06-13T14:02:24+00:00</lastmod>
     </url>
     <url>
         <loc>https://mithrandie.github.io/csvq/license.html</loc>
diff --git a/go.mod b/go.mod
index b50163e..306db36 100644
--- a/go.mod
+++ b/go.mod
@@ -3,7 +3,7 @@ module github.com/mithrandie/csvq
 require (
 	github.com/mitchellh/go-homedir v1.0.0
 	github.com/mithrandie/go-file/v2 v2.0.2
-	github.com/mithrandie/go-text v1.4.0
+	github.com/mithrandie/go-text v1.4.1
 	github.com/mithrandie/readline-csvq v1.1.1
 	github.com/mithrandie/ternary v1.1.0
 	github.com/urfave/cli v1.20.0
diff --git a/go.sum b/go.sum
index 140e4dc..27f24c0 100644
--- a/go.sum
+++ b/go.sum
@@ -2,8 +2,8 @@ github.com/mitchellh/go-homedir v1.0.0 h1:vKb8ShqSby24Yrqr/yDYkuFz8d0WUjys40rvnG
 github.com/mitchellh/go-homedir v1.0.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 github.com/mithrandie/go-file/v2 v2.0.2 h1:3/yzItlTssDX9wOZrj9MtRyXbr52OZURmXFMuvpJ6Fg=
 github.com/mithrandie/go-file/v2 v2.0.2/go.mod h1:98a9loPjYr7ffsfwMDdJ7iH/dO8EXAca8XiI6SZpPV8=
-github.com/mithrandie/go-text v1.4.0 h1:hK2i8ydiM3Uc5UqaY/aNz9ztdlNT8RvBJnJLIOX+tUM=
-github.com/mithrandie/go-text v1.4.0/go.mod h1:Ivtyn3cuJYAs2UpihWmnY1KAixmLonELJ454EOZGzDg=
+github.com/mithrandie/go-text v1.4.1 h1:tLIMamsVRYKsDTIDu7hZifOA4gtwSUln1zrZ9GM0eTU=
+github.com/mithrandie/go-text v1.4.1/go.mod h1:Ivtyn3cuJYAs2UpihWmnY1KAixmLonELJ454EOZGzDg=
 github.com/mithrandie/readline-csvq v1.1.1 h1:kp9W5WPUAB+NOgW5axPdu8mZe1M9CP/D1xpabj39JVY=
 github.com/mithrandie/readline-csvq v1.1.1/go.mod h1:eOJt0j6UI9lhwM/KP+v40ugarhXsnPIXStvkfIaq79E=
 github.com/mithrandie/ternary v1.1.0 h1:BlN8EoTsIYjhuWkfXHrh7+G+/Y0VvvWGVVldyjNH2VU=
diff --git a/lib/json/cache.go b/lib/json/cache.go
index 64ca4c1..61500d3 100644
--- a/lib/json/cache.go
+++ b/lib/json/cache.go
@@ -34,9 +34,6 @@ func (pmap PathMap) load(key string) (PathExpression, bool) {
 
 func (pmap PathMap) Parse(s string) (PathExpression, error) {
 	s = strings.TrimSpace(s)
-	if len(s) < 1 {
-		return nil, nil
-	}
 
 	if e, ok := pmap.load(s); ok {
 		return e, nil
diff --git a/lib/json/conversion_test.go b/lib/json/conversion_test.go
index a5a9945..72c59e6 100644
--- a/lib/json/conversion_test.go
+++ b/lib/json/conversion_test.go
@@ -407,6 +407,48 @@ var convertTableValueToJsonStructureTests = []struct {
 			},
 		},
 	},
+	{
+		Fields: []string{
+			"column1",
+			"",
+		},
+		Rows: [][]value.Primary{
+			{
+				value.NewString("a"),
+				value.NewInteger(1),
+			},
+			{
+				value.NewString("b"),
+				value.NewFloat(0.2),
+			},
+		},
+		Expect: json.Array{
+			json.Object{
+				Members: []json.ObjectMember{
+					{
+						Key:   "column1",
+						Value: json.String("a"),
+					},
+					{
+						Key:   "",
+						Value: json.Integer(1),
+					},
+				},
+			},
+			json.Object{
+				Members: []json.ObjectMember{
+					{
+						Key:   "column1",
+						Value: json.String("b"),
+					},
+					{
+						Key:   "",
+						Value: json.Float(0.2),
+					},
+				},
+			},
+		},
+	},
 	{
 		Fields: []string{
 			"column1",
diff --git a/lib/query/version.go b/lib/query/version.go
index 07b8a0a..ddd3302 100644
--- a/lib/query/version.go
+++ b/lib/query/version.go
@@ -1,3 +1,3 @@
 package query
 
-var Version = "v1.15.1"
+var Version = "v1.15.2"