MDEV-20021 sql_mode="oracle" does not support MINUS set operator

MINUS is mapped to EXCEPT
One consequence of the patch is that MINUS becomes a reserved word in
Oracle mode.

Author: woqutech

mysql-test/suite/compat/oracle/r/minus.result

+CREATE TABLE tx1 (c1 int, c2 varchar(30));
+CREATE TABLE tx2 (c1 int, c2 varchar(30));
+CREATE TABLE tx3 (c1 int, c2 varchar(30));
+INSERT INTO tx1 VALUES (1, 'jim');
+INSERT INTO tx1 VALUES (2, 'menny');
+INSERT INTO tx1 VALUES (3, 'linda');
+INSERT INTO tx2 VALUES (1, 'jim');
+INSERT INTO tx2 VALUES (2, 'kris');
+INSERT INTO tx2 VALUES (3, 'shory');
+INSERT INTO tx3 VALUES (1, 'jim');
+INSERT INTO tx3 VALUES (2, 'kris');
+INSERT INTO tx3 VALUES (3, 'linda');
+#
+# test when sql_mode is not oracle
+#
+SELECT c2 FROM tx1 EXCEPT SELECT c2 from tx2;
+c2
+menny
+linda
+SELECT c2 FROM tx1 MINUS SELECT c2 from tx2;
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'SELECT c2 from tx2' at line 1
+create table MINUS (a int);
+drop table MINUS;
+#
+# test when sql_mode is oracle
+#
+SET sql_mode=ORACLE;
+SELECT c2 FROM tx1 MINUS SELECT c2 from tx2;
+c2
+menny
+linda
+SELECT c2 FROM tx1 MINUS SELECT c2 from tx2 MINUS SELECT c2 from tx3;
+c2
+menny
+SELECT c2 FROM tx1 MINUS SELECT c2 from tx2 EXCEPT SELECT c2 from tx3;
+c2
+menny
+SELECT c2 FROM tx1 MINUS SELECT c2 from tx2 UNION SELECT c2 from tx3;
+c2
+jim
+menny
+linda
+kris
+create table MINUS (a int);
+ERROR 42000: You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'MINUS (a int)' at line 1
+DROP TABLE tx1;
+DROP TABLE tx2;
+DROP TABLE tx3;

mysql-test/suite/compat/oracle/t/minus.test

+CREATE TABLE tx1 (c1 int, c2 varchar(30));
+CREATE TABLE tx2 (c1 int, c2 varchar(30));
+CREATE TABLE tx3 (c1 int, c2 varchar(30));
+INSERT INTO tx1 VALUES (1, 'jim');
+INSERT INTO tx1 VALUES (2, 'menny');
+INSERT INTO tx1 VALUES (3, 'linda');
+
+INSERT INTO tx2 VALUES (1, 'jim');
+INSERT INTO tx2 VALUES (2, 'kris');
+INSERT INTO tx2 VALUES (3, 'shory');
+
+INSERT INTO tx3 VALUES (1, 'jim');
+INSERT INTO tx3 VALUES (2, 'kris');
+INSERT INTO tx3 VALUES (3, 'linda');
+
+--echo #
+--echo # test when sql_mode is not oracle
+--echo #
+
+SELECT c2 FROM tx1 EXCEPT SELECT c2 from tx2;
+--error 1064
+SELECT c2 FROM tx1 MINUS SELECT c2 from tx2;
+
+# MINUS should not be a reserved word
+create table MINUS (a int);
+drop table MINUS;
+
+--echo #
+--echo # test when sql_mode is oracle
+--echo #
+
+SET sql_mode=ORACLE;
+SELECT c2 FROM tx1 MINUS SELECT c2 from tx2;
+SELECT c2 FROM tx1 MINUS SELECT c2 from tx2 MINUS SELECT c2 from tx3;
+SELECT c2 FROM tx1 MINUS SELECT c2 from tx2 EXCEPT SELECT c2 from tx3;
+SELECT c2 FROM tx1 MINUS SELECT c2 from tx2 UNION SELECT c2 from tx3;
+
+# MINUS should be a reserved word
+--error ER_PARSE_ERROR
+create table MINUS (a int);
+
+DROP TABLE tx1;
+DROP TABLE tx2;
+DROP TABLE tx3;
\ No newline at end of file

mysql-test/suite/perfschema/r/start_server_low_digest_sql_length.result

@@ -8,5 +8,5 @@ SELECT 1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1+1
 ####################################
 SELECT event_name, digest, digest_text, sql_text FROM events_statements_history_long;
 event_name	digest	digest_text	sql_text
-statement/sql/select	62764f94ca18cf720c44d84579e05e60	SELECT ? + ? + 	SELECT ...
-statement/sql/truncate	5947880b8ba439f0ed3ff0bfbb04eebf	TRUNCATE TABLE 	truncat...
+statement/sql/select	bb82f2829bcdfd9ac1e53f7b27829d36	SELECT ? + ? + 	SELECT ...
+statement/sql/truncate	fd6a2d48e5fda6a3f990cb8810136546	TRUNCATE TABLE 	truncat...

sql/lex.h

@@ -404,6 +404,7 @@ static SYMBOL symbols[] = {
   { "MICROSECOND",	SYM(MICROSECOND_SYM)},
   { "MIDDLEINT",	SYM(MEDIUMINT)},	/* For powerbuilder */
   { "MIGRATE",          SYM(MIGRATE_SYM)},
+  { "MINUS",            SYM(MINUS_ORACLE_SYM)},
   { "MINUTE",		SYM(MINUTE_SYM)},
   { "MINUTE_MICROSECOND", SYM(MINUTE_MICROSECOND_SYM)},
   { "MINUTE_SECOND",	SYM(MINUTE_SECOND_SYM)},

sql/sql_lex.cc

@@ -1404,6 +1404,7 @@ int Lex_input_stream::find_keyword(Lex_ident_cli_st *kwd,
       case EXCEPTION_MARIADB_SYM:      return EXCEPTION_ORACLE_SYM;
       case EXIT_MARIADB_SYM:           return EXIT_ORACLE_SYM;
       case GOTO_MARIADB_SYM:           return GOTO_ORACLE_SYM;
+      case MINUS_ORACLE_SYM:           return EXCEPT_SYM;
       case NUMBER_MARIADB_SYM:         return NUMBER_ORACLE_SYM;
       case OTHERS_MARIADB_SYM:         return OTHERS_ORACLE_SYM;
       case PACKAGE_MARIADB_SYM:        return PACKAGE_ORACLE_SYM;

sql/sql_yacc.yy

@@ -592,6 +592,7 @@ End SQL_MODE_ORACLE_SPECIFIC */
 %token  <kwd> MEDIUMINT
 %token  <kwd> MEDIUMTEXT
 %token  <kwd> MIN_SYM                       /* SQL-2003-N */
+%token  <kwd> MINUS_ORACLE_SYM              /* Oracle-R   */
 %token  <kwd> MINUTE_MICROSECOND_SYM
 %token  <kwd> MINUTE_SECOND_SYM
 %token  <kwd> MODIFIES_SYM                  /* SQL-2003-R */
@@ -16037,6 +16038,9 @@ keyword_sp_var_and_label:
         | MICROSECOND_SYM
         | MIGRATE_SYM
         | MINUTE_SYM
+/* Start SQL_MODE_DEFAULT_SPECIFIC */
+        | MINUS_ORACLE_SYM
+/* End SQL_MODE_DEFAULT_SPECIFIC */
         | MINVALUE_SYM
         | MIN_ROWS
         | MODIFY_SYM
@@ -16329,6 +16333,9 @@ reserved_keyword_udt_not_param_type:
         | MINUTE_MICROSECOND_SYM
         | MINUTE_SECOND_SYM
         | MIN_SYM
+/* Start SQL_MODE_ORACLE_SPECIFIC
+        | MINUS_ORACLE_SYM
+End SQL_MODE_ORACLE_SPECIFIC */
         | MODIFIES_SYM
         | MOD_SYM
         | NATURAL