[SPARK-14592][SQL] Native support for CREATE TABLE LIKE DDL command

## What changes were proposed in this pull request?
JIRA: https://issues.apache.org/jira/browse/SPARK-14592

This patch adds native support for DDL command `CREATE TABLE LIKE`.

The SQL syntax is like:

    CREATE TABLE table_name LIKE existing_table
    CREATE TABLE IF NOT EXISTS table_name LIKE existing_table

## How was this patch tested?
`HiveDDLCommandSuite`. `HiveQuerySuite` already tests `CREATE TABLE LIKE`.

Author: Liang-Chi Hsieh <simonh@tw.ibm.com>

This patch had conflicts when merged, resolved by
Committer: Andrew Or <andrew@databricks.com>

Closes #12362 from viirya/create-table-like.

1 files changed, 12 insertions, 1 deletions

diff --git a/sql/hive/src/main/scala/org/apache/spark/sql/hive/execution/HiveSqlParser.scala b/sql/hive/src/main/scala/org/apache/spark/sql/hive/execution/HiveSqlParser.scala
index 8c707079a1..a97b65e27b 100644
--- a/sql/hive/src/main/scala/org/apache/spark/sql/hive/execution/HiveSqlParser.scala
+++ b/sql/hive/src/main/scala/org/apache/spark/sql/hive/execution/HiveSqlParser.scala
@@ -31,8 +31,10 @@ import org.apache.spark.sql.catalyst.parser._
 import org.apache.spark.sql.catalyst.parser.SqlBaseParser._
 import org.apache.spark.sql.catalyst.plans.logical.LogicalPlan
 import org.apache.spark.sql.execution.SparkSqlAstBuilder
-import org.apache.spark.sql.execution.command.CreateTable
+import org.apache.spark.sql.execution.command.{CreateTable, CreateTableLike}
 import org.apache.spark.sql.hive.{CreateTableAsSelect => CTAS, CreateViewAsSelect => CreateView, HiveSerDe}
+import org.apache.spark.sql.hive.{HiveGenericUDTF, HiveMetastoreTypes, HiveSerDe}
+import org.apache.spark.sql.hive.HiveShim.HiveFunctionWrapper
 
 /**
  * Concrete parser for HiveQl statements.
@@ -232,6 +234,15 @@ class HiveSqlAstBuilder extends SparkSqlAstBuilder {
   }
 
   /**
+   * Create a [[CreateTableLike]] command.
+   */
+  override def visitCreateTableLike(ctx: CreateTableLikeContext): LogicalPlan = withOrigin(ctx) {
+    val targetTable = visitTableIdentifier(ctx.target)
+    val sourceTable = visitTableIdentifier(ctx.source)
+    CreateTableLike(targetTable, sourceTable, ctx.EXISTS != null)
+  }
+
+  /**
    * Create or replace a view. This creates a [[CreateViewAsSelect]] command.
    *
    * For example: