huaxingao commented on a change in pull request #29396: URL: https://github.com/apache/spark/pull/29396#discussion_r468888891
########## File path: sql/core/src/main/scala/org/apache/spark/sql/execution/datasources/v2/jdbc/JDBCScanBuilder.scala ########## @@ -0,0 +1,61 @@ +/* + * 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.spark.sql.execution.datasources.v2.jdbc + +import org.apache.spark.sql.SparkSession +import org.apache.spark.sql.connector.read.{Scan, ScanBuilder, SupportsPushDownFilters, SupportsPushDownRequiredColumns} +import org.apache.spark.sql.execution.datasources.jdbc.{JDBCOptions, JDBCRDD, JDBCRelation} +import org.apache.spark.sql.jdbc.JdbcDialects +import org.apache.spark.sql.sources.Filter +import org.apache.spark.sql.types.StructType + +case class JDBCScanBuilder( + session: SparkSession, + schema: StructType, + jdbcOptions: JDBCOptions) + extends ScanBuilder with SupportsPushDownFilters with SupportsPushDownRequiredColumns { + + private var pushedFilter = Array.empty[Filter] + + private var prunedSchema = schema + + override def pushFilters(filters: Array[Filter]): Array[Filter] = { + if (jdbcOptions.pushDownPredicate) { + val dialect = JdbcDialects.get(jdbcOptions.url) + val (pushed, unSupported) = filters.partition(JDBCRDD.compileFilter(_, dialect).isDefined) Review comment: I looked the code, seems it doesn't have an easy way to only call `compilefilter` once. After calling `compilefilter` to decide which filters to push down, `buildScan` takes the pushed down filer as an array of source.Filter, which needs to be turned into SQL string filter format by calling `compilefilter` again. ---------------------------------------------------------------- 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: reviews-unsubscr...@spark.apache.org For additional commands, e-mail: reviews-h...@spark.apache.org
