szehon-ho commented on code in PR #55969: URL: https://github.com/apache/spark/pull/55969#discussion_r3276377369
########## sql/pipelines/src/test/scala/org/apache/spark/sql/pipelines/autocdc/Scd1BatchProcessorSuite.scala: ########## @@ -0,0 +1,366 @@ +/* + * 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.pipelines.autocdc + +import org.apache.spark.sql.QueryTest +import org.apache.spark.sql.{functions => F, Row} +import org.apache.spark.sql.classic.DataFrame +import org.apache.spark.sql.test.SharedSparkSession +import org.apache.spark.sql.types._ + +class Scd1BatchProcessorSuite extends QueryTest with SharedSparkSession { + + /** Build a microbatch [[DataFrame]] from explicit rows and an explicit schema. */ + private def microbatchOf(schema: StructType)(rows: Row*): DataFrame = + spark.createDataFrame(spark.sparkContext.parallelize(rows), schema) + + /** + * Returns the `(name, dataType)` pairs of `schema`'s fields. Used to compare two schemas for + * structural equivalence while deliberately ignoring nullability and metadata, which can shift + * benignly when columns are unpacked from a struct. + */ + private def columnNamesAndDataTypes(schema: StructType): Seq[(String, DataType)] = + schema.fields.map(f => (f.name, f.dataType)).toSeq + + test("deduplicateMicrobatch keeps only the row with the largest sequence value per key") { + val schema = new StructType() + .add("id", IntegerType) + .add("seq", LongType) + .add("value", StringType) + + val batch = microbatchOf(schema)( + Row(1, 10L, "first"), + Row(1, 30L, "winner"), + Row(1, 20L, "middle") + ) + + val processor = Scd1BatchProcessor( + changeArgs = ChangeArgs( + keys = Seq(UnqualifiedColumnName("id")), + sequencing = F.col("seq"), + storedAsScdType = ScdType.Type1 + ) + ) + + checkAnswer( + df = processor.deduplicateMicrobatch(batch), + expectedAnswer = Row(1, 30L, "winner") + ) + } + + test("deduplicateMicrobatch is no-op if there's a single event for a key") { + val schema = new StructType() + .add("id", IntegerType) + .add("seq", LongType) + .add("value", StringType) + + val batch = microbatchOf(schema)( + Row(1, 10L, "only-row") + ) + + val processor = Scd1BatchProcessor( + changeArgs = ChangeArgs( + keys = Seq(UnqualifiedColumnName("id")), + sequencing = F.col("seq"), + storedAsScdType = ScdType.Type1 + ) + ) + + checkAnswer( + df = processor.deduplicateMicrobatch(batch), + expectedAnswer = Row(1, 10L, "only-row") + ) + } + + test("deduplicateMicrobatch handles equal sequencing values for the same key") { Review Comment: Good that this documents the tie contract (one survivor, value non-deterministic). To make that contract harder to regress, consider strengthening the test — e.g. run `deduplicateMicrobatch` twice on the same input and assert `length == 1` both times (and optionally that the survivor is still one of the tied values). We do not need to assert the same row twice, but a second invocation makes "exactly one row per key" explicit beyond a single `collect()`. -- 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: [email protected] For queries about this service, please contact Infrastructure at: [email protected] --------------------------------------------------------------------- To unsubscribe, e-mail: [email protected] For additional commands, e-mail: [email protected]
