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ASF GitHub Bot commented on FLINK-4565: --------------------------------------- Github user twalthr commented on a diff in the pull request: https://github.com/apache/flink/pull/4404#discussion_r131655114 --- Diff: flink-libraries/flink-table/src/main/scala/org/apache/flink/table/expressions/subquery.scala --- @@ -0,0 +1,95 @@ +/* + * 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 com.google.common.collect.ImmutableList +import org.apache.calcite.rex.{RexNode, RexSubQuery} +import org.apache.calcite.sql.fun.SqlStdOperatorTable +import org.apache.calcite.tools.RelBuilder +import org.apache.flink.api.common.typeinfo.BasicTypeInfo._ +import org.apache.flink.api.common.typeinfo.TypeInformation +import org.apache.flink.table.api.StreamTableEnvironment +import org.apache.flink.table.typeutils.TypeCheckUtils._ +import org.apache.flink.table.validate.{ValidationFailure, ValidationResult, ValidationSuccess} + +case class In(expression: Expression, elements: Seq[Expression]) extends Expression { + + override def toString = s"$expression.in(${elements.mkString(", ")})" + + override private[flink] def children: Seq[Expression] = expression +: elements.distinct + + override private[flink] def toRexNode(implicit relBuilder: RelBuilder): RexNode = { + // check if this is a sub-query expression or an element list + elements.head match { + + case TableReference(name, table) => + RexSubQuery.in(table.getRelNode, ImmutableList.of(expression.toRexNode)) + + case _ => + relBuilder.call(SqlStdOperatorTable.IN, children.map(_.toRexNode): _*) + } + } + + override private[flink] def validateInput(): ValidationResult = { + // check if this is a sub-query expression or an element list + elements.head match { + + case TableReference(name, table) => + if (elements.length != 1) { + return ValidationFailure("IN operator supports only one table reference.") + } + if (table.tableEnv.isInstanceOf[StreamTableEnvironment]) { + return ValidationFailure( + "Sub-query IN operator on stream tables is currently not supported.") + } + val tableOutput = table.logicalPlan.output + if (tableOutput.length > 1) { + return ValidationFailure( + s"The sub-query table '$name' must not have more than one column.") + } + (expression.resultType, tableOutput.head.resultType) match { + case (lType, rType) if isNumeric(lType) && isNumeric(rType) => ValidationSuccess + case (lType, rType) if lType == rType => ValidationSuccess --- End diff -- I think a hotfix is enough. This part is not performance critical anyway, because it happens before runtime. > Support for SQL IN operator > --------------------------- > > Key: FLINK-4565 > URL: https://issues.apache.org/jira/browse/FLINK-4565 > Project: Flink > Issue Type: Improvement > Components: Table API & SQL > Reporter: Timo Walther > Assignee: Timo Walther > Fix For: 1.4.0 > > > It seems that Flink SQL supports the uncorrelated sub-query IN operator. But > it should also be available in the Table API and tested. -- This message was sent by Atlassian JIRA (v6.4.14#64029)