qingwei91 commented on code in PR #20140: URL: https://github.com/apache/flink/pull/20140#discussion_r1008835739
########## flink-connectors/flink-connector-jdbc/src/main/java/org/apache/flink/connector/jdbc/table/JdbcFilterPushdownPreparedStatementVisitor.java: ########## @@ -0,0 +1,185 @@ +/* + * 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.connector.jdbc.table; + +import org.apache.flink.annotation.Experimental; +import org.apache.flink.table.expressions.CallExpression; +import org.apache.flink.table.expressions.Expression; +import org.apache.flink.table.expressions.ExpressionDefaultVisitor; +import org.apache.flink.table.expressions.FieldReferenceExpression; +import org.apache.flink.table.expressions.ResolvedExpression; +import org.apache.flink.table.expressions.ValueLiteralExpression; +import org.apache.flink.table.functions.BuiltInFunctionDefinitions; +import org.apache.flink.table.types.logical.BigIntType; +import org.apache.flink.table.types.logical.BooleanType; +import org.apache.flink.table.types.logical.DateType; +import org.apache.flink.table.types.logical.DecimalType; +import org.apache.flink.table.types.logical.DoubleType; +import org.apache.flink.table.types.logical.FloatType; +import org.apache.flink.table.types.logical.IntType; +import org.apache.flink.table.types.logical.LogicalType; +import org.apache.flink.table.types.logical.SmallIntType; +import org.apache.flink.table.types.logical.TimeType; +import org.apache.flink.table.types.logical.TimestampType; +import org.apache.flink.table.types.logical.VarCharType; + +import java.io.Serializable; +import java.math.BigDecimal; +import java.sql.Date; +import java.sql.Timestamp; +import java.time.LocalDate; +import java.time.LocalDateTime; +import java.util.HashSet; +import java.util.List; +import java.util.Optional; +import java.util.Set; +import java.util.function.Function; + +/** + * Visitor that convert Expression to ParameterizedPredicate. Return Optional.empty() if we cannot + * push down the filter. + */ +@Experimental +public class JdbcFilterPushdownPreparedStatementVisitor + extends ExpressionDefaultVisitor<Optional<ParameterizedPredicate>> { + + private Function<String, String> quoteIdentifierFunction; + + private static final Set<Class<?>> SUPPORTED_DATA_TYPES; + + static { + SUPPORTED_DATA_TYPES = new HashSet<>(); + SUPPORTED_DATA_TYPES.add(IntType.class); + SUPPORTED_DATA_TYPES.add(BigIntType.class); + SUPPORTED_DATA_TYPES.add(BooleanType.class); + SUPPORTED_DATA_TYPES.add(DecimalType.class); + SUPPORTED_DATA_TYPES.add(DoubleType.class); + SUPPORTED_DATA_TYPES.add(FloatType.class); + SUPPORTED_DATA_TYPES.add(SmallIntType.class); + SUPPORTED_DATA_TYPES.add(VarCharType.class); + SUPPORTED_DATA_TYPES.add(TimestampType.class); + SUPPORTED_DATA_TYPES.add(DateType.class); + SUPPORTED_DATA_TYPES.add(TimeType.class); + } + + public JdbcFilterPushdownPreparedStatementVisitor( + Function<String, String> quoteIdentifierFunction) { + this.quoteIdentifierFunction = quoteIdentifierFunction; + } + + @Override + public Optional<ParameterizedPredicate> visit(CallExpression call) { + if (BuiltInFunctionDefinitions.EQUALS.equals(call.getFunctionDefinition())) { + return renderBinaryOperator("=", call.getResolvedChildren()); + } + if (BuiltInFunctionDefinitions.LESS_THAN.equals(call.getFunctionDefinition())) { + return renderBinaryOperator("<", call.getResolvedChildren()); + } + if (BuiltInFunctionDefinitions.LESS_THAN_OR_EQUAL.equals(call.getFunctionDefinition())) { + return renderBinaryOperator("<=", call.getResolvedChildren()); + } + if (BuiltInFunctionDefinitions.GREATER_THAN.equals(call.getFunctionDefinition())) { + return renderBinaryOperator(">", call.getResolvedChildren()); + } + if (BuiltInFunctionDefinitions.GREATER_THAN_OR_EQUAL.equals(call.getFunctionDefinition())) { + return renderBinaryOperator(">=", call.getResolvedChildren()); + } + if (BuiltInFunctionDefinitions.NOT_EQUALS.equals(call.getFunctionDefinition())) { + return renderBinaryOperator("<>", call.getResolvedChildren()); + } + if (BuiltInFunctionDefinitions.OR.equals(call.getFunctionDefinition())) { + return renderBinaryOperator("OR", call.getResolvedChildren()); + } + if (BuiltInFunctionDefinitions.AND.equals(call.getFunctionDefinition())) { + return renderBinaryOperator("AND", call.getResolvedChildren()); + } + + return Optional.empty(); + } + + private Optional<ParameterizedPredicate> renderBinaryOperator( + String operator, List<ResolvedExpression> allOperands) { + Optional<ParameterizedPredicate> leftOperandString = allOperands.get(0).accept(this); + + Optional<ParameterizedPredicate> rightOperandString = allOperands.get(1).accept(this); + + return leftOperandString.flatMap( + left -> rightOperandString.map(right -> left.combine(operator, right))); + } + + @Override + public Optional<ParameterizedPredicate> visit(ValueLiteralExpression litExp) { + LogicalType tpe = litExp.getOutputDataType().getLogicalType(); + Class<?> typeCs = tpe.getClass(); + + if (SUPPORTED_DATA_TYPES.contains(typeCs)) { Review Comment: Great idea! I didnt discover this typeRoot thingy earlier, thanks for the suggestion. https://github.com/apache/flink/pull/20140/commits/dd54aedb1a71eb66fc37857c86a0c8e32ff8e4b6 -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: issues-unsubscr...@flink.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org
