Bug #30234: Unexpected behavior using DELETE with AS and USING

  
DELETE FROM ... USING ... statements with the following type of 
ambiguous aliasing gave unexpected results:
DELETE FROM t1 AS alias USING t1, t2 AS alias WHERE t1.a = alias.a;
This query would leave table t1 intact but delete rows from t2.
Fixed by changing DELETE FROM ... USING syntax so that only alias 
references (as opposed to alias declarations) may be used in FROM.


mysql-test/r/delete.result:
  Bug#30234: Test Result
mysql-test/t/delete.test:
  Bug#30234: Test Case
sql/sql_yacc.yy:
  Bug#30234:
  - Added parser rule table_alias_ref_list that contains a list of table 
    aliases only.
  - Added parser rule table_alias_ref that sets the TL_OPTION_ALIAS in 
    order to turn off semantic checking that applies only for table names.

1 files changed, 44 insertions, 0 deletions

diff --git a/mysql-test/t/delete.test b/mysql-test/t/delete.test
index 36d627209db..e3713d248c4 100644
--- a/mysql-test/t/delete.test
+++ b/mysql-test/t/delete.test
@@ -221,3 +221,47 @@ DELETE FROM t1 ORDER BY t2.x;
 DELETE FROM t1 ORDER BY (SELECT x);
 
 DROP TABLE t1;
+
+#
+# Bug #30234: Unexpected behavior using DELETE with AS and USING
+# '
+CREATE TABLE t1 (
+  a INT
+);
+
+CREATE TABLE t2 (
+  a INT
+);
+
+CREATE DATABASE db1;
+CREATE TABLE db1.t1 (
+  a INT
+);
+INSERT INTO db1.t1 (a) SELECT * FROM t1;
+
+CREATE DATABASE db2;
+CREATE TABLE db2.t1 (
+  a INT
+);
+INSERT INTO db2.t1 (a) SELECT * FROM t2;
+
+--error ER_PARSE_ERROR
+DELETE FROM t1 alias USING t1, t2 alias WHERE t1.a = alias.a;
+DELETE FROM alias USING t1, t2 alias WHERE t1.a = alias.a;
+DELETE FROM t1, alias USING t1, t2 alias WHERE t1.a = alias.a;
+--error ER_UNKNOWN_TABLE
+DELETE FROM t1, t2 USING t1, t2 alias WHERE t1.a = alias.a;
+--error ER_PARSE_ERROR
+DELETE FROM db1.t1 alias USING db1.t1, db2.t1 alias WHERE db1.t1.a = alias.a;
+--error ER_UNKNOWN_TABLE
+DELETE FROM alias USING db1.t1, db2.t1 alias WHERE db1.t1.a = alias.a;
+DELETE FROM db2.alias USING db1.t1, db2.t1 alias WHERE db1.t1.a = alias.a;
+DELETE FROM t1 USING t1 WHERE a = 1;
+SELECT * FROM t1;
+--error ER_PARSE_ERROR
+DELETE FROM t1 alias USING t1 alias WHERE a = 2;
+SELECT * FROM t1;
+
+DROP TABLE t1, t2;
+DROP DATABASE db1;
+DROP DATABASE db2;