[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[asfgit]

Github user asfgit closed the pull request at:

https://github.com/apache/flink/pull/4078


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[haohui]

Github user haohui commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r126870195
  
--- Diff: flink-libraries/flink-table/pom.xml ---
@@ -110,6 +110,11 @@ under the License.
 compile
 
 
+   
+   joda-time
+   joda-time
--- End diff --

There is a explicit version in the pom.xml at the root level.


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[haohui]

Github user haohui commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r126870280
  
--- Diff: 
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/codegen/CodeGenerator.scala
 ---
@@ -2008,6 +2008,33 @@ class CodeGenerator(
   }
 
   /**
+* Adds a reusable [[java.util.Random]] to the member area of the 
generated [[Function]].
+*
+* The seed parameter must be a literal/constant expression.
+*
+* @return member variable term
+*/
+  def addReusableDateFormatter(format: GeneratedExpression): String = {
+val fieldTerm = newName("dateFormatter")
+
+val field =
+  s"""
+ |transient org.joda.time.format.DateTimeFormatter $fieldTerm;
+ |""".stripMargin
+reusableMemberStatements.add(field)
+
+val fieldInit =
+  s"""
+ |${format.code}
+ |$fieldTerm = org.apache.flink.table.runtime.functions.
+ 
|DateTimeFunctions$$.MODULE$$.createDateTimeFormatter(${format.resultTerm});
--- End diff --

This is because the runtime ``DateTimeFunctions`` has been ported to Scala. 
This is the syntax to access the function.


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[fhueske]

Github user fhueske commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r126747879
  
--- Diff: 
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/codegen/calls/DateFormatCallGen.scala
 ---
@@ -0,0 +1,44 @@
+/*
+ * 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.
+ */
+
+package org.apache.flink.table.codegen.calls
+
+import org.apache.flink.api.common.typeinfo.BasicTypeInfo._
+import org.apache.flink.table.codegen.{CodeGenerator, GeneratedExpression}
+import 
org.apache.flink.table.codegen.calls.CallGenerator.generateCallIfArgsNotNull
+
+class DateFormatCallGen extends CallGenerator {
+  override def generate(codeGenerator: CodeGenerator,
+operands: Seq[GeneratedExpression])
+  : GeneratedExpression = {
+
+if (operands.last.literal) {
+  val formatter = codeGenerator.addReusableDateFormatter(operands.last)
+  generateCallIfArgsNotNull(codeGenerator.nullCheck, STRING_TYPE_INFO, 
operands) {
+terms =>s"$formatter.print(${terms.head})"
--- End diff --

+space between `=>` and `s`


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[fhueske]

Github user fhueske commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r126750513
  
--- Diff: 
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/validate/FunctionCatalog.scala
 ---
@@ -374,6 +375,7 @@ class BasicOperatorTable extends 
ReflectiveSqlOperatorTable {
 SqlStdOperatorTable.CURRENT_TIME,
 SqlStdOperatorTable.CURRENT_TIMESTAMP,
 SqlStdOperatorTable.CURRENT_DATE,
+DateTimeSqlFunction.DATE_FORMAT,
--- End diff --

The new function should also be added to the documentation (Table API + 
SQL).


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[fhueske]

Github user fhueske commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r126747178
  
--- Diff: 
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/codegen/CodeGenerator.scala
 ---
@@ -2008,6 +2008,33 @@ class CodeGenerator(
   }
 
   /**
+* Adds a reusable [[java.util.Random]] to the member area of the 
generated [[Function]].
+*
+* The seed parameter must be a literal/constant expression.
+*
+* @return member variable term
+*/
+  def addReusableDateFormatter(format: GeneratedExpression): String = {
+val fieldTerm = newName("dateFormatter")
+
+val field =
+  s"""
+ |transient org.joda.time.format.DateTimeFormatter $fieldTerm;
+ |""".stripMargin
+reusableMemberStatements.add(field)
+
+val fieldInit =
+  s"""
+ |${format.code}
+ |$fieldTerm = org.apache.flink.table.runtime.functions.
+ 
|DateTimeFunctions$$.MODULE$$.createDateTimeFormatter(${format.resultTerm});
--- End diff --

What is `$$.MODULE$$`?


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[fhueske]

Github user fhueske commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r126748981
  
--- Diff: 
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/functions/DateTimeSqlFunction.scala
 ---
@@ -0,0 +1,34 @@
+/*
+ * 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.
+ */
+
+package org.apache.flink.table.functions
+
+import org.apache.calcite.sql.`type`._
+import org.apache.calcite.sql.{SqlFunction, SqlFunctionCategory, SqlKind}
+
+
+object DateTimeSqlFunction {
--- End diff --

It seems that this class has been copied to 
`org.apache.flink.table.functions.sql` as suggested by @twalthr. I assume this 
version can be deleted, right?


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[fhueske]

Github user fhueske commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r126746604
  
--- Diff: 
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/codegen/CodeGenerator.scala
 ---
@@ -2008,6 +2008,33 @@ class CodeGenerator(
   }
 
   /**
+* Adds a reusable [[java.util.Random]] to the member area of the 
generated [[Function]].
--- End diff --

`java.util.Random` -> `DataTimeFormatter`


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[fhueske]

Github user fhueske commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r126746348
  
--- Diff: flink-libraries/flink-table/pom.xml ---
@@ -110,6 +110,11 @@ under the License.
 compile
 
 
+   
+   joda-time
+   joda-time
--- End diff --

Where is the `joda-time` version inferred from?


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[fhueske]

Github user fhueske commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r126747228
  
--- Diff: 
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/codegen/calls/BuiltInMethods.scala
 ---
@@ -89,5 +89,4 @@ object BuiltInMethods {
   val CONCAT_WS =
 Types.lookupMethod(
   classOf[ScalarFunctions], "concat_ws", classOf[String], 
classOf[Array[String]])
-
--- End diff --

remove unrelated change


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[fhueske]

Github user fhueske commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r126746651
  
--- Diff: 
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/codegen/CodeGenerator.scala
 ---
@@ -2008,6 +2008,33 @@ class CodeGenerator(
   }
 
   /**
+* Adds a reusable [[java.util.Random]] to the member area of the 
generated [[Function]].
+*
+* The seed parameter must be a literal/constant expression.
--- End diff --

The format parameter must be a literal/constant expression.


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[twalthr]

Github user twalthr commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r123717228
  
--- Diff: 
flink-libraries/flink-table/src/test/scala/org/apache/flink/table/expressions/DateTimeFunctionTest.scala
 ---
@@ -0,0 +1,49 @@
+/*
+ * 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.
+ */
+
+package org.apache.flink.table.expressions
+
+import java.sql.Timestamp
+
+import org.apache.flink.api.common.typeinfo.{TypeInformation, Types}
+import org.apache.flink.api.java.typeutils.RowTypeInfo
+import org.apache.flink.table.api.scala._
+import org.apache.flink.table.expressions.utils.ExpressionTestBase
+import org.apache.flink.types.Row
+import org.junit.Test
+
+class DateTimeFunctionTest extends ExpressionTestBase {
+
+  @Test
+  def testDateFormat(): Unit = {
--- End diff --

Can you add 2 or 3 more complicated tests?


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[twalthr]

Github user twalthr commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r123718414
  
--- Diff: 
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/expressions/time.scala
 ---
@@ -375,3 +377,13 @@ case class TemporalOverlaps(
   }
 }
 
+case class DateFormat(timestamp: Expression, format: Expression) extends 
Expression {
+  override private[flink] def children = timestamp :: format :: Nil
+
+  override private[flink] def toRexNode(implicit relBuilder: RelBuilder) =
+relBuilder.call(DateTimeSqlFunction.DATE_FORMAT, timestamp.toRexNode, 
format.toRexNode)
+
+  override def toString: String = s"$timestamp.dateformat($format)"
--- End diff --

`dateFormat`


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[twalthr]

Github user twalthr commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r123718210
  
--- Diff: 
flink-libraries/flink-table/src/main/java/org/apache/flink/table/runtime/DateTimeFunctions.java
 ---
@@ -0,0 +1,158 @@
+/*
+ * 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.
+ */
+
+package org.apache.flink.table.runtime;
--- End diff --

I would move this into a separate package. Maybe 
`org.apache.flink.table.runtime.functions`. I think there will be more 
functions of this kind soon.


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[twalthr]

Github user twalthr commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r123718165
  
--- Diff: 
flink-libraries/flink-table/src/main/java/org/apache/flink/table/runtime/DateTimeFunctions.java
 ---
@@ -0,0 +1,158 @@
+/*
+ * 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.
+ */
+
+package org.apache.flink.table.runtime;
+
+import org.joda.time.format.DateTimeFormatter;
+import org.joda.time.format.DateTimeFormatterBuilder;
+
+/**
+ * Built-in scalar functions for date time related operations.
+ */
+public class DateTimeFunctions {
+   private static final int PIVOT_YEAR = 2020;
+
+   private static final ThreadLocalCache 
DATETIME_FORMATTER_CACHE =
+   new ThreadLocalCache(100) {
+   @Override
+   protected DateTimeFormatter getNewInstance(String 
format) {
+   return createDateTimeFormatter(format);
+   }
+   };
+
+   public static String dateFormat(long ts, String formatString) {
+   DateTimeFormatter formatter = 
DATETIME_FORMATTER_CACHE.get(formatString);
--- End diff --

I recently added a `literal` flag to generated expressions. So we can check 
if the parameters of a constructor are constant (see `RandCallGen`). Would be 
great if you could also change `RandCallGen` to use the ThreadLocalCache if 
seed is not constant. 


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[twalthr]

Github user twalthr commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r123718616
  
--- Diff: 
flink-libraries/flink-table/src/main/scala/org/apache/flink/table/functions/DateTimeSqlFunction.scala
 ---
@@ -0,0 +1,34 @@
+/*
+ * 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.
+ */
+
+package org.apache.flink.table.functions
--- End diff --

I would move this to `org.apache.flink.table.functions.sql`. There will be 
more functions of this kind in the future.


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[fhueske]

Github user fhueske commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r122254102
  
--- Diff: 
flink-libraries/flink-table/src/test/scala/org/apache/flink/table/expressions/DateTimeFunctionTest.scala
 ---
@@ -0,0 +1,49 @@
+/*
+ * 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.
+ */
+
+package org.apache.flink.table.expressions
+
+import java.sql.Timestamp
+
+import org.apache.flink.api.common.typeinfo.{TypeInformation, Types}
+import org.apache.flink.api.java.typeutils.RowTypeInfo
+import org.apache.flink.table.api.scala._
+import org.apache.flink.table.expressions.utils.ExpressionTestBase
+import org.apache.flink.types.Row
+import org.junit.Test
+
+class DateTimeFunctionTest extends ExpressionTestBase {
+
+  @Test
+  def testDateFormat(): Unit = {
+testAllApis(
+  DateFormat('f0, "%Y"),
--- End diff --

I think it would be good to have a pattern that uses all features. 


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[fhueske]

Github user fhueske commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r122240819
  
--- Diff: 
flink-libraries/flink-table/src/main/java/org/apache/flink/table/runtime/DateTimeFunctions.java
 ---
@@ -0,0 +1,158 @@
+/*
+ * 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.
+ */
+
+package org.apache.flink.table.runtime;
+
+import org.joda.time.format.DateTimeFormatter;
+import org.joda.time.format.DateTimeFormatterBuilder;
+
+/**
+ * Built-in scalar functions for date time related operations.
+ */
+public class DateTimeFunctions {
--- End diff --

We try to keep the code base of the Table API consistently in Scala. There 
are a few classes in Java which are mostly copied from Calcite.
Can you port this class?


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[fhueske]

Github user fhueske commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r122255933
  
--- Diff: flink-libraries/flink-table/pom.xml ---
@@ -110,6 +110,12 @@ under the License.
 compile
 
 
+   
+   joda-time
+   joda-time
+   provided
--- End diff --

Why is `joda-time` provided? Is it a transitive dependency?


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[fhueske]

Github user fhueske commented on a diff in the pull request:

https://github.com/apache/flink/pull/4078#discussion_r122255414
  
--- Diff: 
flink-libraries/flink-table/src/main/java/org/apache/flink/table/runtime/DateTimeFunctions.java
 ---
@@ -0,0 +1,158 @@
+/*
+ * 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.
+ */
+
+package org.apache.flink.table.runtime;
+
+import org.joda.time.format.DateTimeFormatter;
+import org.joda.time.format.DateTimeFormatterBuilder;
+
+/**
+ * Built-in scalar functions for date time related operations.
+ */
+public class DateTimeFunctions {
+   private static final int PIVOT_YEAR = 2020;
+
+   private static final ThreadLocalCache 
DATETIME_FORMATTER_CACHE =
+   new ThreadLocalCache(100) {
+   @Override
+   protected DateTimeFormatter getNewInstance(String 
format) {
+   return createDateTimeFormatter(format);
+   }
+   };
+
+   public static String dateFormat(long ts, String formatString) {
+   DateTimeFormatter formatter = 
DATETIME_FORMATTER_CACHE.get(formatString);
--- End diff --

Would it make sense to add a shortcut during code-gen if the pattern is a 
string literal (this should be the most common case) to avoid the lookup?


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[GitHub] flink pull request #4078: [FLINK-6693] [table] Support DATE_FORMAT function ...

[haohui]

GitHub user haohui opened a pull request:

https://github.com/apache/flink/pull/4078

[FLINK-6693] [table] Support DATE_FORMAT function in the Table / SQL API.



You can merge this pull request into a Git repository by running:

$ git pull https://github.com/haohui/flink FLINK-6693

Alternatively you can review and apply these changes as the patch at:

https://github.com/apache/flink/pull/4078.patch

To close this pull request, make a commit to your master/trunk branch
with (at least) the following in the commit message:

This closes #4078


commit 64f706adecec16b1592943bbd1780b3d222a220f
Author: Haohui Mai 
Date:   2017-06-06T06:23:31Z

[FLINK-6693] [table] Support DATE_FORMAT function in the Table / SQL API.




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