siddharthteotia commented on a change in pull request #6998: URL: https://github.com/apache/incubator-pinot/pull/6998#discussion_r648420886
########## File path: pinot-core/src/main/java/org/apache/pinot/core/query/optimizer/statement/JsonStatementOptimizer.java ########## @@ -0,0 +1,436 @@ +/** + * 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.pinot.core.query.optimizer.statement; + +import java.lang.reflect.Method; +import java.util.ArrayList; +import java.util.HashSet; +import java.util.List; +import java.util.Locale; +import java.util.Set; +import javax.annotation.Nullable; +import org.apache.pinot.common.function.scalar.ArithmeticFunctions; +import org.apache.pinot.common.request.Expression; +import org.apache.pinot.common.request.ExpressionType; +import org.apache.pinot.common.request.Function; +import org.apache.pinot.common.request.Identifier; +import org.apache.pinot.common.request.Literal; +import org.apache.pinot.common.request.PinotQuery; +import org.apache.pinot.common.utils.request.RequestUtils; +import org.apache.pinot.pql.parsers.pql2.ast.FilterKind; +import org.apache.pinot.pql.parsers.pql2.ast.FloatingPointLiteralAstNode; +import org.apache.pinot.pql.parsers.pql2.ast.LiteralAstNode; +import org.apache.pinot.pql.parsers.pql2.ast.StringLiteralAstNode; +import org.apache.pinot.segment.spi.AggregationFunctionType; +import org.apache.pinot.spi.data.FieldSpec; +import org.apache.pinot.spi.data.Schema; +import org.apache.pinot.spi.utils.Pair; + + +/** + * This class will rewrite a query that has json path expressions into a query that uses JSON_EXTRACT_SCALAR and + * JSON_MATCH functions. + * + * Example 1: + * From : SELECT jsonColumn.name.first + * FROM testTable + * WHERE jsonColumn.name.first IS NOT NULL + * TO : SELECT JSON_EXTRACT_SCALAR(jsonColumn, '$.name.first', 'STRING', 'null') AS jsonColum.name.first + * FROM testTable + * WHERE JSON_MATCH('"$.name.first" IS NOT NULL') + * + * Output datatype of any json path expression is 'STRING'. However, if json path expression appears as an argument to + * a numerical function, then output of json path expression is set to 'DOUBLE' as shown in the example below. + * + * Example 2: + * From: SELECT MIN(jsonColumn.id - 5) + * FROM testTable + * WHERE jsonColumn.id IS NOT NULL + * To: SELECT MIN(MINUS(JSON_EXTRACT_SCALAR(jsonColumn, '$.id', 'DOUBLE', '-Infinity'),5)) AS min(minus(jsonColum.id, '5')) + * FROM testTable + * WHERE JSON_MATCH('"$.id" IS NOT NULL') + * + * Example 3: + * From: SELECT jsonColumn.id, count(*) + * FROM testTable + * WHERE jsonColumn.name.first = 'Daffy' OR jsonColumn.id > 10 + * GROUP BY jsonColumn.id + * To: SELECT MIN(JSON_EXTRACT_SCALAR(jsonColumn, '$.id', 'DOUBLE', '-Infinity')) AS min(jsonColumn.id) + * FROM testTable + * WHERE JSON_MATCH('"$.name.first" = ''Daffy''') OR JSON_MATCH('"$.id" = 10') + * GROUP BY JSON_EXTRACT_SCALAR(jsonColumn, '$.id', 'STRING', 'null'); + * + * Example 4: + * From: SELECT jsonColumn.name.last, count(*) + * FROM testTable + * GROUP BY jsonColumn.name.last + * HAVING jsonColumn.name.last = 'mouse' + * To: SELECT JSON_EXTRACT_SCALAR(jsonColumn, '$.name.last', 'STRING', 'null') AS jsonColumn.name.last, count(*) + * FROM testTable + * GROUP BY JSON_EXTRACT_SCALAR(jsonColumn, '$.name.last', 'STRING', 'null') + * HAVING JSON_EXTRACT_SCALAR(jsonColumn, '$.name.last', 'STRING', 'null') = 'mouse' + * + * Notes: + * 1) In a filter expression, if json path appears on the left-hand side, the right-hand side must be a literal. In + * future this can be changed to have any expression on the right-hand side by implementing a function that would + * convert any {@link Expression} into SQL fragment that can be used in JSON_MATCH. Currently only literals are Review comment: SQL fragment ? FWIW, fragment is a commonly used terminology for a unit of work in distributed query execution engines (see Presto docs for example). -- 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. For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@pinot.apache.org For additional commands, e-mail: commits-h...@pinot.apache.org
