diff --git a/sql/core/src/main/scala/org/apache/spark/sql/catalyst/SQLBuilder.scala b/sql/core/src/main/scala/org/apache/spark/sql/catalyst/SQLBuilder.scala index 6f821f80cc4c582259c5492d882b46f79d86e792..380454267eaf44a4901c0631c724caaf71363142 100644 --- a/sql/core/src/main/scala/org/apache/spark/sql/catalyst/SQLBuilder.scala +++ b/sql/core/src/main/scala/org/apache/spark/sql/catalyst/SQLBuilder.scala @@ -138,9 +138,14 @@ class SQLBuilder private ( case g: Generate => generateToSQL(g) - case Limit(limitExpr, child) => + // This prevents a pattern of `((...) AS gen_subquery_0 LIMIT 1)` which does not work. + // For example, `SELECT * FROM (SELECT id FROM tbl TABLESAMPLE (2 ROWS))` makes this plan. + case Limit(limitExpr, child: SubqueryAlias) => s"${toSQL(child)} LIMIT ${limitExpr.sql}" + case Limit(limitExpr, child) => + s"(${toSQL(child)} LIMIT ${limitExpr.sql})" + case Filter(condition, child) => val whereOrHaving = child match { case _: Aggregate => "HAVING" diff --git a/sql/hive/src/test/resources/sqlgen/generate_with_other_1.sql b/sql/hive/src/test/resources/sqlgen/generate_with_other_1.sql index ab444d0c7093653a8a2fd729578fc04374610cd1..0739f8fff54672f4dac3e1d5c02789d93aaf9256 100644 --- a/sql/hive/src/test/resources/sqlgen/generate_with_other_1.sql +++ b/sql/hive/src/test/resources/sqlgen/generate_with_other_1.sql @@ -5,4 +5,4 @@ WHERE id > 2 ORDER BY val, id LIMIT 5 -------------------------------------------------------------------------------- -SELECT `gen_attr_0` AS `val`, `gen_attr_1` AS `id` FROM (SELECT `gen_attr_0`, `gen_attr_1` FROM (SELECT gen_subquery_0.`gen_attr_2`, gen_subquery_0.`gen_attr_3`, gen_subquery_0.`gen_attr_4`, gen_subquery_0.`gen_attr_1` FROM (SELECT `arr` AS `gen_attr_2`, `arr2` AS `gen_attr_3`, `json` AS `gen_attr_4`, `id` AS `gen_attr_1` FROM `default`.`parquet_t3`) AS gen_subquery_0 WHERE (`gen_attr_1` > CAST(2 AS BIGINT))) AS gen_subquery_1 LATERAL VIEW explode(`gen_attr_2`) gen_subquery_2 AS `gen_attr_0` ORDER BY `gen_attr_0` ASC NULLS FIRST, `gen_attr_1` ASC NULLS FIRST LIMIT 5) AS parquet_t3 +SELECT `gen_attr_0` AS `val`, `gen_attr_1` AS `id` FROM ((SELECT `gen_attr_0`, `gen_attr_1` FROM (SELECT gen_subquery_0.`gen_attr_2`, gen_subquery_0.`gen_attr_3`, gen_subquery_0.`gen_attr_4`, gen_subquery_0.`gen_attr_1` FROM (SELECT `arr` AS `gen_attr_2`, `arr2` AS `gen_attr_3`, `json` AS `gen_attr_4`, `id` AS `gen_attr_1` FROM `default`.`parquet_t3`) AS gen_subquery_0 WHERE (`gen_attr_1` > CAST(2 AS BIGINT))) AS gen_subquery_1 LATERAL VIEW explode(`gen_attr_2`) gen_subquery_2 AS `gen_attr_0` ORDER BY `gen_attr_0` ASC NULLS FIRST, `gen_attr_1` ASC NULLS FIRST LIMIT 5)) AS parquet_t3 diff --git a/sql/hive/src/test/resources/sqlgen/generate_with_other_2.sql b/sql/hive/src/test/resources/sqlgen/generate_with_other_2.sql index 42a2369f34d1ce7efc992dc429d62ecd7e4b23a2..c4b344ee238a51dc3edaa4d7948f148e583bd2f3 100644 --- a/sql/hive/src/test/resources/sqlgen/generate_with_other_2.sql +++ b/sql/hive/src/test/resources/sqlgen/generate_with_other_2.sql @@ -7,4 +7,4 @@ WHERE val > 2 ORDER BY val, id LIMIT 5 -------------------------------------------------------------------------------- -SELECT `gen_attr_0` AS `val`, `gen_attr_1` AS `id` FROM (SELECT `gen_attr_0`, `gen_attr_1` FROM (SELECT `arr` AS `gen_attr_4`, `arr2` AS `gen_attr_3`, `json` AS `gen_attr_5`, `id` AS `gen_attr_1` FROM `default`.`parquet_t3`) AS gen_subquery_0 LATERAL VIEW explode(`gen_attr_3`) gen_subquery_2 AS `gen_attr_2` LATERAL VIEW explode(`gen_attr_2`) gen_subquery_3 AS `gen_attr_0` WHERE (`gen_attr_0` > CAST(2 AS BIGINT)) ORDER BY `gen_attr_0` ASC NULLS FIRST, `gen_attr_1` ASC NULLS FIRST LIMIT 5) AS gen_subquery_1 +SELECT `gen_attr_0` AS `val`, `gen_attr_1` AS `id` FROM ((SELECT `gen_attr_0`, `gen_attr_1` FROM (SELECT `arr` AS `gen_attr_4`, `arr2` AS `gen_attr_3`, `json` AS `gen_attr_5`, `id` AS `gen_attr_1` FROM `default`.`parquet_t3`) AS gen_subquery_0 LATERAL VIEW explode(`gen_attr_3`) gen_subquery_2 AS `gen_attr_2` LATERAL VIEW explode(`gen_attr_2`) gen_subquery_3 AS `gen_attr_0` WHERE (`gen_attr_0` > CAST(2 AS BIGINT)) ORDER BY `gen_attr_0` ASC NULLS FIRST, `gen_attr_1` ASC NULLS FIRST LIMIT 5)) AS gen_subquery_1 diff --git a/sql/hive/src/test/resources/sqlgen/limit.sql b/sql/hive/src/test/resources/sqlgen/limit.sql new file mode 100644 index 0000000000000000000000000000000000000000..7a6b060fbf505108d893b7d296e98d95b34b066b --- /dev/null +++ b/sql/hive/src/test/resources/sqlgen/limit.sql @@ -0,0 +1,4 @@ +-- This file is automatically generated by LogicalPlanToSQLSuite. +SELECT * FROM (SELECT id FROM tbl LIMIT 2) +-------------------------------------------------------------------------------- +SELECT `gen_attr_0` AS `id` FROM (SELECT `gen_attr_0` FROM (SELECT `gen_attr_0` FROM (SELECT `id` AS `gen_attr_0`, `name` AS `gen_attr_1` FROM `default`.`tbl`) AS gen_subquery_0 LIMIT 2)) AS tbl diff --git a/sql/hive/src/test/scala/org/apache/spark/sql/catalyst/LogicalPlanToSQLSuite.scala b/sql/hive/src/test/scala/org/apache/spark/sql/catalyst/LogicalPlanToSQLSuite.scala index 8696337b9dc8aa2ecfec3921dda11ed52ab8cc71..557ea44d1c80b6feeb9d7c43c782516a76799a4c 100644 --- a/sql/hive/src/test/scala/org/apache/spark/sql/catalyst/LogicalPlanToSQLSuite.scala +++ b/sql/hive/src/test/scala/org/apache/spark/sql/catalyst/LogicalPlanToSQLSuite.scala @@ -1173,4 +1173,14 @@ class LogicalPlanToSQLSuite extends SQLBuilderTest with SQLTestUtils { ) } } + + test("SPARK-17982 - limit") { + withTable("tbl") { + sql("CREATE TABLE tbl(id INT, name STRING)") + checkSQL( + "SELECT * FROM (SELECT id FROM tbl LIMIT 2)", + "limit" + ) + } + } }