Add CINE option for CREATE TABLE AS and CREATE MATERIALIZED VIEW

Fabrízio de Royes Mello reviewed by Rushabh Lathia.

4 files changed, 47 insertions, 0 deletions

diff --git a/src/backend/commands/createas.c b/src/backend/commands/createas.c
index 5e0ac585603..72315c2f3fc 100644
--- a/src/backend/commands/createas.c
+++ b/src/backend/commands/createas.c
@@ -28,6 +28,7 @@
 #include "access/sysattr.h"
 #include "access/xact.h"
 #include "access/xlog.h"
+#include "catalog/namespace.h"
 #include "catalog/toasting.h"
 #include "commands/createas.h"
 #include "commands/matview.h"
@@ -86,6 +87,22 @@ ExecCreateTableAs(CreateTableAsStmt *stmt, const char *queryString,
 	QueryDesc  *queryDesc;
 	ScanDirection dir;
 
+	if (stmt->if_not_exists)
+	{
+		Oid	nspid;
+
+		nspid = RangeVarGetCreationNamespace(stmt->into->rel);
+
+		if (get_relname_relid(stmt->into->rel->relname, nspid))
+		{
+			ereport(NOTICE,
+					(errcode(ERRCODE_DUPLICATE_TABLE),
+					 errmsg("relation \"%s\" already exists, skipping",
+							stmt->into->rel->relname)));
+			return InvalidOid;
+		}
+	}
+
 	/*
 	 * Create the tuple receiver object and insert info it will need
 	 */
diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c
index 6b1bf7be19d..491e4db9d6f 100644
--- a/src/backend/nodes/copyfuncs.c
+++ b/src/backend/nodes/copyfuncs.c
@@ -3317,6 +3317,7 @@ _copyCreateTableAsStmt(const CreateTableAsStmt *from)
 	COPY_NODE_FIELD(into);
 	COPY_SCALAR_FIELD(relkind);
 	COPY_SCALAR_FIELD(is_select_into);
+	COPY_SCALAR_FIELD(if_not_exists);
 
 	return newnode;
 }
diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c
index d5db71d3a86..08036743d57 100644
--- a/src/backend/nodes/equalfuncs.c
+++ b/src/backend/nodes/equalfuncs.c
@@ -1530,6 +1530,7 @@ _equalCreateTableAsStmt(const CreateTableAsStmt *a, const CreateTableAsStmt *b)
 	COMPARE_NODE_FIELD(into);
 	COMPARE_SCALAR_FIELD(relkind);
 	COMPARE_SCALAR_FIELD(is_select_into);
+	COMPARE_SCALAR_FIELD(if_not_exists);
 
 	return true;
 }
diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y
index 4b5009b636d..1f4fe9d4943 100644
--- a/src/backend/parser/gram.y
+++ b/src/backend/parser/gram.y
@@ -3401,11 +3401,25 @@ CreateAsStmt:
 					ctas->into = $4;
 					ctas->relkind = OBJECT_TABLE;
 					ctas->is_select_into = false;
+					ctas->if_not_exists = false;
 					/* cram additional flags into the IntoClause */
 					$4->rel->relpersistence = $2;
 					$4->skipData = !($7);
 					$$ = (Node *) ctas;
 				}
+		| CREATE OptTemp TABLE IF_P NOT EXISTS create_as_target AS SelectStmt opt_with_data
+				{
+					CreateTableAsStmt *ctas = makeNode(CreateTableAsStmt);
+					ctas->query = $9;
+					ctas->into = $7;
+					ctas->relkind = OBJECT_TABLE;
+					ctas->is_select_into = false;
+					ctas->if_not_exists = true;
+					/* cram additional flags into the IntoClause */
+					$7->rel->relpersistence = $2;
+					$7->skipData = !($10);
+					$$ = (Node *) ctas;
+				}
 		;
 
 create_as_target:
@@ -3444,11 +3458,25 @@ CreateMatViewStmt:
 					ctas->into = $5;
 					ctas->relkind = OBJECT_MATVIEW;
 					ctas->is_select_into = false;
+					ctas->if_not_exists = false;
 					/* cram additional flags into the IntoClause */
 					$5->rel->relpersistence = $2;
 					$5->skipData = !($8);
 					$$ = (Node *) ctas;
 				}
+		| CREATE OptNoLog MATERIALIZED VIEW IF_P NOT EXISTS create_mv_target AS SelectStmt opt_with_data
+				{
+					CreateTableAsStmt *ctas = makeNode(CreateTableAsStmt);
+					ctas->query = $10;
+					ctas->into = $8;
+					ctas->relkind = OBJECT_MATVIEW;
+					ctas->is_select_into = false;
+					ctas->if_not_exists = true;
+					/* cram additional flags into the IntoClause */
+					$8->rel->relpersistence = $2;
+					$8->skipData = !($11);
+					$$ = (Node *) ctas;
+				}
 		;
 
 create_mv_target: