[SPARK-19723][SQL] create datasource table with an non-existent location should work

## What changes were proposed in this pull request?

This JIRA is a follow up work after [SPARK-19583](https://issues.apache.org/jira/browse/SPARK-19583)

As we discussed in that [PR](https://github.com/apache/spark/pull/16938)

The following DDL for datasource table with an non-existent location should work:
```
CREATE TABLE ... (PARTITIONED BY ...) LOCATION path
```
Currently it will throw exception that path not exists for datasource table for datasource table

## How was this patch tested?
unit test added

Author: windpiger <songjun@outlook.com>

Closes #17055 from windpiger/CTDataSourcePathNotExists.

2 files changed, 67 insertions, 42 deletions

diff --git a/sql/core/src/main/scala/org/apache/spark/sql/execution/command/createDataSourceTables.scala b/sql/core/src/main/scala/org/apache/spark/sql/execution/command/createDataSourceTables.scala
index 3da66afced..2d890118ae 100644
--- a/sql/core/src/main/scala/org/apache/spark/sql/execution/command/createDataSourceTables.scala
+++ b/sql/core/src/main/scala/org/apache/spark/sql/execution/command/createDataSourceTables.scala
@@ -73,7 +73,8 @@ case class CreateDataSourceTableCommand(table: CatalogTable, ignoreIfExists: Boo
         className = table.provider.get,
         bucketSpec = table.bucketSpec,
         options = table.storage.properties ++ pathOption,
-        catalogTable = Some(tableWithDefaultOptions)).resolveRelation()
+        // As discussed in SPARK-19583, we don't check if the location is existed
+        catalogTable = Some(tableWithDefaultOptions)).resolveRelation(checkFilesExist = false)
 
     val partitionColumnNames = if (table.schema.nonEmpty) {
       table.partitionColumnNames
diff --git a/sql/core/src/test/scala/org/apache/spark/sql/execution/command/DDLSuite.scala b/sql/core/src/test/scala/org/apache/spark/sql/execution/command/DDLSuite.scala
index 5f70a8ce89..0666f446f3 100644
--- a/sql/core/src/test/scala/org/apache/spark/sql/execution/command/DDLSuite.scala
+++ b/sql/core/src/test/scala/org/apache/spark/sql/execution/command/DDLSuite.scala
@@ -230,7 +230,7 @@ abstract class DDLSuite extends QueryTest with SQLTestUtils {
   }
 
   private def getDBPath(dbName: String): URI = {
-    val warehousePath = makeQualifiedPath(s"${spark.sessionState.conf.warehousePath}")
+    val warehousePath = makeQualifiedPath(spark.sessionState.conf.warehousePath)
     new Path(CatalogUtils.URIToString(warehousePath), s"$dbName.db").toUri
   }
 
@@ -1899,7 +1899,7 @@ abstract class DDLSuite extends QueryTest with SQLTestUtils {
     }
   }
 
-  test("insert data to a data source table which has a not existed location should succeed") {
+  test("insert data to a data source table which has a non-existing location should succeed") {
     withTable("t") {
       withTempDir { dir =>
         spark.sql(
@@ -1939,7 +1939,7 @@ abstract class DDLSuite extends QueryTest with SQLTestUtils {
     }
   }
 
-  test("insert into a data source table with no existed partition location should succeed") {
+  test("insert into a data source table with a non-existing partition location should succeed") {
     withTable("t") {
       withTempDir { dir =>
         spark.sql(
@@ -1966,7 +1966,7 @@ abstract class DDLSuite extends QueryTest with SQLTestUtils {
     }
   }
 
-  test("read data from a data source table which has a not existed location should succeed") {
+  test("read data from a data source table which has a non-existing location should succeed") {
     withTable("t") {
       withTempDir { dir =>
         spark.sql(
@@ -1994,7 +1994,7 @@ abstract class DDLSuite extends QueryTest with SQLTestUtils {
     }
   }
 
-  test("read data from a data source table with no existed partition location should succeed") {
+  test("read data from a data source table with non-existing partition location should succeed") {
     withTable("t") {
       withTempDir { dir =>
         spark.sql(
@@ -2016,48 +2016,72 @@ abstract class DDLSuite extends QueryTest with SQLTestUtils {
     }
   }
 
+  test("create datasource table with a non-existing location") {
+    withTable("t", "t1") {
+      withTempPath { dir =>
+        spark.sql(s"CREATE TABLE t(a int, b int) USING parquet LOCATION '$dir'")
+
+        val table = spark.sessionState.catalog.getTableMetadata(TableIdentifier("t"))
+        assert(table.location == makeQualifiedPath(dir.getAbsolutePath))
+
+        spark.sql("INSERT INTO TABLE t SELECT 1, 2")
+        assert(dir.exists())
+
+        checkAnswer(spark.table("t"), Row(1, 2))
+      }
+      // partition table
+      withTempPath { dir =>
+        spark.sql(s"CREATE TABLE t1(a int, b int) USING parquet PARTITIONED BY(a) LOCATION '$dir'")
+
+        val table = spark.sessionState.catalog.getTableMetadata(TableIdentifier("t1"))
+        assert(table.location == makeQualifiedPath(dir.getAbsolutePath))
+
+        spark.sql("INSERT INTO TABLE t1 PARTITION(a=1) SELECT 2")
+
+        val partDir = new File(dir, "a=1")
+        assert(partDir.exists())
+
+        checkAnswer(spark.table("t1"), Row(2, 1))
+      }
+    }
+  }
+
   Seq(true, false).foreach { shouldDelete =>
-    val tcName = if (shouldDelete) "non-existent" else "existed"
+    val tcName = if (shouldDelete) "non-existing" else "existed"
     test(s"CTAS for external data source table with a $tcName location") {
       withTable("t", "t1") {
-        withTempDir {
-          dir =>
-            if (shouldDelete) {
-              dir.delete()
-            }
-            spark.sql(
-              s"""
-                 |CREATE TABLE t
-                 |USING parquet
-                 |LOCATION '$dir'
-                 |AS SELECT 3 as a, 4 as b, 1 as c, 2 as d
-               """.stripMargin)
-            val table = spark.sessionState.catalog.getTableMetadata(TableIdentifier("t"))
-            assert(table.location == makeQualifiedPath(dir.getAbsolutePath))
+        withTempDir { dir =>
+          if (shouldDelete) dir.delete()
+          spark.sql(
+            s"""
+               |CREATE TABLE t
+               |USING parquet
+               |LOCATION '$dir'
+               |AS SELECT 3 as a, 4 as b, 1 as c, 2 as d
+             """.stripMargin)
+          val table = spark.sessionState.catalog.getTableMetadata(TableIdentifier("t"))
+          assert(table.location == makeQualifiedPath(dir.getAbsolutePath))
 
-            checkAnswer(spark.table("t"), Row(3, 4, 1, 2))
+          checkAnswer(spark.table("t"), Row(3, 4, 1, 2))
         }
         // partition table
-        withTempDir {
-          dir =>
-            if (shouldDelete) {
-              dir.delete()
-            }
-            spark.sql(
-              s"""
-                 |CREATE TABLE t1
-                 |USING parquet
-                 |PARTITIONED BY(a, b)
-                 |LOCATION '$dir'
-                 |AS SELECT 3 as a, 4 as b, 1 as c, 2 as d
-               """.stripMargin)
-            val table = spark.sessionState.catalog.getTableMetadata(TableIdentifier("t1"))
-            assert(table.location == makeQualifiedPath(dir.getAbsolutePath))
-
-            val partDir = new File(dir, "a=3")
-            assert(partDir.exists())
-
-            checkAnswer(spark.table("t1"), Row(1, 2, 3, 4))
+        withTempDir { dir =>
+          if (shouldDelete) dir.delete()
+          spark.sql(
+            s"""
+               |CREATE TABLE t1
+               |USING parquet
+               |PARTITIONED BY(a, b)
+               |LOCATION '$dir'
+               |AS SELECT 3 as a, 4 as b, 1 as c, 2 as d
+             """.stripMargin)
+          val table = spark.sessionState.catalog.getTableMetadata(TableIdentifier("t1"))
+          assert(table.location == makeQualifiedPath(dir.getAbsolutePath))
+
+          val partDir = new File(dir, "a=3")
+          assert(partDir.exists())
+
+          checkAnswer(spark.table("t1"), Row(1, 2, 3, 4))
         }
       }
     }