dtenedor commented on a change in pull request #35855:
URL: https://github.com/apache/spark/pull/35855#discussion_r828313396
##########
File path:
sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/ResolveInlineTables.scala
##########
@@ -20,21 +20,31 @@ package org.apache.spark.sql.catalyst.analysis
import scala.util.control.NonFatal
import org.apache.spark.sql.catalyst.InternalRow
-import org.apache.spark.sql.catalyst.plans.logical.{LocalRelation, LogicalPlan}
+import org.apache.spark.sql.catalyst.catalog.SessionCatalog
+import org.apache.spark.sql.catalyst.plans.logical.{InsertIntoStatement,
LocalRelation, LogicalPlan, Project}
import org.apache.spark.sql.catalyst.rules.Rule
import org.apache.spark.sql.catalyst.trees.AlwaysProcess
import org.apache.spark.sql.types.{StructField, StructType}
/**
* An analyzer rule that replaces [[UnresolvedInlineTable]] with
[[LocalRelation]].
*/
-object ResolveInlineTables extends Rule[LogicalPlan] with CastSupport {
+case class ResolveInlineTables(catalog: SessionCatalog) extends
Rule[LogicalPlan] with CastSupport {
override def apply(plan: LogicalPlan): LogicalPlan =
plan.resolveOperatorsWithPruning(
AlwaysProcess.fn, ruleId) {
case table: UnresolvedInlineTable if table.expressionsResolved =>
validateInputDimension(table)
validateInputEvaluable(table)
convert(table)
+ case i @ InsertIntoStatement(_, _, _, (_: UnresolvedInlineTable | _:
Project), _, _) =>
+ // This case matches against an INSERT INTO statement whose right-hand
side is either a
+ // VALUES list (comprising an inline table) or else a SELECT query
(comprising a projection).
+ // In either case, we expect this input to be unresolved at this point
because this
+ // [[ResolveInlineTables]] rule runs top-down. It is necessary to match
against the entire
+ // INSERT INTO statement in this way in order to provide enough context
to know what values
+ // to replace each explicit provided DEFAULT reference with.
+ DefaultColumns.ReplaceExplicitDefaultColumnValues(
Review comment:
Good idea, that simplifies things :) done.
##########
File path:
sql/catalyst/src/main/scala/org/apache/spark/sql/catalyst/analysis/DefaultColumns.scala
##########
@@ -0,0 +1,287 @@
+/*
+ * 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.catalyst.analysis
+
+import org.apache.spark.sql.AnalysisException
+import org.apache.spark.sql.catalyst.TableIdentifier
+import org.apache.spark.sql.catalyst.catalog._
+import org.apache.spark.sql.catalyst.expressions.{Expression, _}
+import org.apache.spark.sql.catalyst.optimizer.ConstantFolding
+import org.apache.spark.sql.catalyst.parser.{CatalystSqlParser, ParseException}
+import org.apache.spark.sql.catalyst.plans.logical._
+import org.apache.spark.sql.types._
+
+/**
+ * This class contains logic for processing DEFAULT columns in statements such
as CREATE TABLE.
+ */
+object DefaultColumns {
+ val default = "default"
+ val analysisPrefix =
+ " has a DEFAULT value which fails to resolve to a valid constant
expression: "
+ val columnDefaultNotFound = "Column 'default' does not exist"
+ lazy val parser = new CatalystSqlParser()
+ lazy val analyzer =
+ new Analyzer(new SessionCatalog(new InMemoryCatalog,
FunctionRegistry.builtin))
+
+ /**
+ * Finds DEFAULT expressions in CREATE/REPLACE TABLE commands and
constant-folds then.
+ *
+ * Example:
+ * CREATE TABLE T(a INT, b INT DEFAULT 5 + 5) becomes
+ * CREATE TABLE T(a INT, b INT DEFAULT 10)
+ *
+ * @param tableSchema represents the names and types of the columns of the
statement to process.
+ * @param statementType name of the statement being processed, such as
INSERT; useful for errors.
+ * @return a copy of `tableSchema` with field metadata updated with the
constant-folded values.
+ */
+ def ConstantFoldDefaultExpressions(tableSchema: StructType, statementType:
String): StructType = {
+ // Get the list of column indexes in the CREATE TABLE command with DEFAULT
values.
+ val (fields: Array[StructField], indexes: Array[Int]) =
+ tableSchema.fields.zipWithIndex.filter { case (f, i) =>
f.metadata.contains(default) }.unzip
+ // Extract the list of DEFAULT column values from the CreateTable command.
+ val colNames: Seq[String] = fields.map { _.name }
+ val defaults: Seq[String] = fields.map { _.metadata.getString(default) }
+ // Extract the list of DEFAULT column values from the CreateTable command.
+ val exprs: Seq[Expression] = colNames.zip(defaults).map {
+ case (name, text) => Parse(name, text, statementType)
+ }
+ // Analyze and constant-fold each parse result.
+ val analyzed: Seq[Expression] = (exprs, defaults, colNames).zipped.map {
+ case (expr, default, name) => Analyze(expr, default, name, statementType)
+ }
+ // Create a map from the column index of each DEFAULT column to its type.
+ val indexMap: Map[Int, StructField] = (indexes, fields,
analyzed).zipped.map {
+ case (index, field, expr) =>
+ val newMetadata: Metadata = new
MetadataBuilder().withMetadata(field.metadata)
+ .putString(default, expr.sql).build()
+ (index, field.copy(metadata = newMetadata))
+ }.toMap
+ // Finally, replace the original struct fields with the new ones.
+ val newFields: Seq[StructField] =
+ tableSchema.fields.zipWithIndex.map { case (f, i) =>
indexMap.getOrElse(i, f) }
+ StructType(newFields)
+ }
+
+ /**
+ * Adds a projection over the plan in `insert.query` generating missing
default column values.
+ *
+ * @param insert the INSERT INTO statement to add missing DEFAULT column
references to.
+ * @param catalog the catalog to use for looking up the schema of the INSERT
INTO table object.
+ * @return the updated statement with missing DEFAULT column values appended
to the list.
+ */
+ def AddProjectionForMissingDefaultColumnValues(
+ insert: InsertIntoStatement, catalog: SessionCatalog):
InsertIntoStatement = {
+ // Compute the number of attributes returned by the INSERT INTO statement.
+ val numQueryOutputs: Int = insert.query match {
+ case table: UnresolvedInlineTable
+ if table.rows.nonEmpty && table.rows.forall(_.size ==
table.rows(0).size) =>
+ table.rows(0).size
+ case project: Project => project.projectList.size
+ case _ => return insert
+ }
+ // The table value provides the DEFAULT column values as text; analyze
them into expressions.
+ val schema: StructType = getInsertTableSchema(insert,
catalog).getOrElse(return insert)
+ val schemaWithoutPartitionCols =
StructType(schema.fields.dropRight(insert.partitionSpec.size))
+ val coerced: Seq[Expression] = for {
+ field <- schemaWithoutPartitionCols.fields.drop(numQueryOutputs)
+ name: String = field.name
+ text: String =
+ if (field.metadata.contains(default))
field.metadata.getString(default) else "NULL"
+ // Parse the DEFAULT column expression. If the parsing fails, throw an
error to the user.
+ expr: Expression = Parse(name, text, "INSERT")
+ // Analyze and constant-fold each result.
+ analyzed: Expression = Analyze(expr, text, name, "INSERT")
+ // Perform implicit coercion from the provided expression type to the
required column type.
+ errorPrefix = "Failed to execute INSERT command because the destination
table column "
+ coerced: Expression =
+ if (field.dataType == analyzed.dataType) {
+ analyzed
+ } else if (Cast.canUpCast(analyzed.dataType, field.dataType)) {
+ Cast(analyzed, field.dataType)
+ } else {
+ throw new AnalysisException(errorPrefix +
+ s"$name has a DEFAULT value with type ${field.dataType}, but the "
+
+ s"query provided a value of incompatible type
${analyzed.dataType}")
+ }
+ } yield coerced
+ // Finally, return a projection of the original `insert.query` output
attributes plus new
+ // aliases over the DEFAULT column values.
+ // If the insertQuery is an existing Project, flatten them together.
+ val newQuery = insert.query match {
+ case Project(projectList, child) =>
+ val newAliases: Seq[NamedExpression] =
coerced.zip(schemaWithoutPartitionCols.fields).map {
+ case (expr, field) => Alias(expr, field.name)() }
+ Project(projectList ++ newAliases, child)
+ case table: UnresolvedInlineTable =>
+ val newNames: Seq[String] =
+ schemaWithoutPartitionCols.fields.drop(numQueryOutputs).map { _.name
}
+ table.copy(names = table.names ++ newNames, rows = table.rows.map {
row => row ++ coerced })
+ case _ => insert.query
+ }
+ insert.copy(query = newQuery)
+ }
+
+ /**
+ * Replaces unresolved "DEFAULT" column references with matching default
column values.
+ *
+ * Background: CREATE TABLE and ALTER TABLE invocations support setting
column default values for
+ * later operations. Following INSERT, and INSERT MERGE commands may then
reference the value
+ * using the DEFAULT keyword as needed.
+ *
+ * Example:
+ * CREATE TABLE T(a INT DEFAULT 4, b INT NOT NULL DEFAULT 5);
+ * INSERT INTO T VALUES (1, 2);
+ * INSERT INTO T VALUES (1, DEFAULT);
+ * INSERT INTO T VALUES (DEFAULT, 6);
+ * SELECT * FROM T;
+ * (1, 2)
+ * (1, 5)
+ * (4, 6)
+ *
+ * @param insert the INSERT INTO statement to replace explicit DEFAULT
column references within.
+ * @param catalog the catalog to use for looking up the schema of the INSERT
INTO table object.
+ * @return the updated statement with DEFAULT column references replaced
with their values.
+ */
+ def ReplaceExplicitDefaultColumnValues(
+ insert: InsertIntoStatement, catalog: SessionCatalog):
InsertIntoStatement = {
+ // Extract the list of DEFAULT column values from the INSERT INTO
statement.
+ val schema: StructType = getInsertTableSchema(insert,
catalog).getOrElse(return insert)
+ val schemaWithoutPartitionCols =
StructType(schema.fields.dropRight(insert.partitionSpec.size))
+ val colNames: Seq[String] = schemaWithoutPartitionCols.fields.map { _.name
}
+ val defaultExprs: Seq[Expression] = schemaWithoutPartitionCols.fields.map {
+ case f if f.metadata.contains(default) =>
+ parser.parseExpression(f.metadata.getString(default))
+ case _ => Literal(null)
+ }
+ // Handle two types of logical query plans in the target of the INSERT
INTO statement:
+ // Inline table: VALUES (0, 1, DEFAULT, ...)
+ // Projection: SELECT 0, 1, DEFAULT, ...
+ // Note that the DEFAULT reference may not participate in complex
expressions such as
+ // "DEFAULT + 2"; this generally results in a "not found" error later in
the analyzer.
+ val newQuery: LogicalPlan = insert.query match {
+ case table: UnresolvedInlineTable
+ if table.rows.nonEmpty && table.rows.forall(_.size ==
defaultExprs.size) =>
+ val newRows: Seq[Seq[Expression]] =
+ table.rows.map { row: Seq[Expression] =>
+ // Map each row of the VALUES list to its corresponding DEFAULT
expression in the
+ // INSERT INTO object table, if the two lists are equal in length.
+ row.zip(defaultExprs).map {
+ case (expr: Expression, defaultExpr: Expression) =>
+ expr match {
+ case u: UnresolvedAttribute if
u.name.equalsIgnoreCase(default) => defaultExpr
+ case _ => expr
+ }
+ }
+ }
+ table.copy(rows = newRows)
+ case project: Project if project.projectList.size == defaultExprs.size =>
+ val updated: Seq[NamedExpression] =
+ // Map each expression of the project list to its corresponding
DEFAULT expression in the
+ // INSERT INTO object table, if the two lists are equal in length.
+ (project.projectList, defaultExprs, colNames).zipped.map {
+ case (expr: Expression, defaultExpr: Expression, colName: String)
=>
+ expr match {
+ case u: UnresolvedAttribute if
u.name.equalsIgnoreCase(default) =>
+ Alias(defaultExpr, colName)()
+ case _ => expr
+ }
+ }
+ project.copy(projectList = updated)
+ case _ => insert.query
+ }
+ insert.copy(query = newQuery)
+ }
+
+ /**
+ * Parses DEFAULT column text to an expression, returning a reasonable error
upon failure.
+ *
+ * @param colName the name of the DEFAULT column whose text we endeavor to
parse.
+ * @param colText the string contents of the DEFAULT column value.
+ * @param statementType which type of statement we are running, such as
INSERT; useful for errors.
+ * @return the expression resulting from the parsing step.
+ */
+ private def Parse(colName: String, colText: String, statementType: String):
Expression = {
+ try {
+ parser.parseExpression(colText)
+ } catch {
+ case ex: ParseException =>
+ throw new AnalysisException(
+ s"Failed to execute $statementType command because the destination
table column " +
+ colName + analysisPrefix + s"$colText yields ${ex.getMessage}")
+ }
+ }
+
+ /**
+ * Analyzes and constant-folds `colExpr`, returning a reasonable error
message upon failure.
+ *
+ * @param colExpr result of a parsing operation suitable for consumption by
analysis.
+ * @param colText string contents of the DEFAULT column value; useful for
errors.
+ * @param colName string name of the DEFAULT column; useful for errors.
+ * @param statementType which type of statement we are running, such as
INSERT; useful for errors.
+ * @return Result of the analysis and constant-folding operation.
+ */
+ private def Analyze(colExpr: Expression, colText: String, colName: String,
+ statementType: String):
+ Expression = {
+ try {
+ // Invoke the analyzer over the 'colExpr'.
+ val plan = analyzer.execute(Project(Seq(Alias(colExpr, colName)()),
OneRowRelation()))
+ analyzer.checkAnalysis(plan)
+ // Perform constant folding over the result.
+ val folded = ConstantFolding(plan)
+ val result = folded match {
+ case Project(Seq(a: Alias), OneRowRelation()) => a.child
+ }
+ // Make sure the constant folding was successful.
Review comment:
I was doing this for the INSERT INTO statements but not CREATE/REPLACE
TABLE statements during constant-folding. This is a good point, I moved the
type coercion logic into the 'analyze' helper method so it always runs.
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