[FLINK-20765] ScalarOperatorGens doesn't set proper nullability for result type of generated expressions

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.16.0
• Component/s: Table SQL / Runtime
• Labels: auto-deprioritized-major auto-deprioritized-minor pull-request-available stale-major
• Assignee: luoyuxia
• Reporter: Rui Li
• Created: 25/Dec/20 02:35
• Updated: 17/Jun/22 11:37
• Resolved: 17/Jun/22 11:37

Description

Suppose we have a function that takes a BOOLEAN NOT NULL parameter:

	/**
	 * A function that takes BOOLEAN NOT NULL.
	 */
	public static class BoolEcho extends ScalarFunction {
		public Boolean eval(@DataTypeHint("BOOLEAN NOT NULL") Boolean b) {
			return b;
		}
	}

Then the following test case will fail:

CREATE TABLE SourceTable(x INT NOT NULL,y INT) WITH ('connector' = 'COLLECTION');
SELECT BoolEcho(x=1 and y is null) FROM SourceTable;

with exception:

org.apache.flink.table.planner.codegen.CodeGenException: Mismatch of function's argument data type 'BOOLEAN NOT NULL' and actual argument type 'BOOLEAN'.

	at org.apache.flink.table.planner.codegen.calls.BridgingFunctionGenUtil$$anonfun$verifyArgumentTypes$1.apply(BridgingFunctionGenUtil.scala:323)
	at org.apache.flink.table.planner.codegen.calls.BridgingFunctionGenUtil$$anonfun$verifyArgumentTypes$1.apply(BridgingFunctionGenUtil.scala:320)
	at scala.collection.mutable.ResizableArray$class.foreach(ResizableArray.scala:59)
	at scala.collection.mutable.ArrayBuffer.foreach(ArrayBuffer.scala:48)
	at org.apache.flink.table.planner.codegen.calls.BridgingFunctionGenUtil$.verifyArgumentTypes(BridgingFunctionGenUtil.scala:320)
	at org.apache.flink.table.planner.codegen.calls.BridgingFunctionGenUtil$.generateFunctionAwareCallWithDataType(BridgingFunctionGenUtil.scala:95)
	at org.apache.flink.table.planner.codegen.calls.BridgingFunctionGenUtil$.generateFunctionAwareCall(BridgingFunctionGenUtil.scala:65)
	at org.apache.flink.table.planner.codegen.calls.BridgingSqlFunctionCallGen.generate(BridgingSqlFunctionCallGen.scala:62)
	at org.apache.flink.table.planner.codegen.ExprCodeGenerator.generateCallExpression(ExprCodeGenerator.scala:832)
	at org.apache.flink.table.planner.codegen.ExprCodeGenerator.visitCall(ExprCodeGenerator.scala:529)
	at org.apache.flink.table.planner.codegen.ExprCodeGenerator.visitCall(ExprCodeGenerator.scala:56)
	at org.apache.calcite.rex.RexCall.accept(RexCall.java:174)
	at org.apache.flink.table.planner.codegen.ExprCodeGenerator.generateExpression(ExprCodeGenerator.scala:155)

Issue Links

• duplicates: FLINK-25095 Case when would be translated into different expression in Hive dialect and default dialect
• duplicates: FLINK-26363 Fail to use such expression like if(1= 1, 2, 3)
• is related to: FLINK-25095 Case when would be translated into different expression in Hive dialect and default dialect
• links to: GitHub Pull Request #19851