MDEV-9144 JSON data type

for compatibility with MySQL, add 'JSON' as an alias for 'TEXT'

mysql-test/r/type_json.result

+create or replace table t1(a json);
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` text DEFAULT NULL
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+create or replace table t1(a json character set utf8 default '{a:1}');
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` text CHARACTER SET utf8 DEFAULT '{a:1}'
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+create or replace table t1(a json binary not null check (json_valid(a)));
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` text CHARACTER SET latin1 COLLATE latin1_bin NOT NULL CHECK (json_valid(`a`))
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+insert t1 values ('[]');
+insert t1 values ('a');
+ERROR 23000: CONSTRAINT `a` failed for `test`.`t1`
+set timestamp=unix_timestamp('2010:11:12 13:14:15');
+create or replace table t1(a json default(json_object('now', now())));
+show create table t1;
+Table	Create Table
+t1	CREATE TABLE `t1` (
+  `a` text DEFAULT json_object('now',current_timestamp())
+) ENGINE=MyISAM DEFAULT CHARSET=latin1
+insert t1 values ();
+select * from t1;
+a
+{"now": "2010-11-12 13:14:15"}
+drop table t1;
+select cast('{a:1}' as text);
+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 'text)' at line 1
+select cast('{a:1}' as json);
+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 'json)' at line 1

mysql-test/t/type_json.test

+#
+# MDEV-9144 JSON data type
+#
+
+create or replace table t1(a json);
+show create table t1;
+
+create or replace table t1(a json character set utf8 default '{a:1}');
+show create table t1;
+
+create or replace table t1(a json binary not null check (json_valid(a)));
+show create table t1;
+insert t1 values ('[]');
+--error ER_CONSTRAINT_FAILED
+insert t1 values ('a');
+
+set timestamp=unix_timestamp('2010:11:12 13:14:15');
+create or replace table t1(a json default(json_object('now', now())));
+show create table t1;
+insert t1 values ();
+select * from t1;
+
+drop table t1;
+
+--error ER_PARSE_ERROR
+select cast('{a:1}' as text);
+--error ER_PARSE_ERROR
+select cast('{a:1}' as json);

sql/sql_yacc.yy

@@ -6478,6 +6478,8 @@ field_type:
           { $$.set(MYSQL_TYPE_SET); }
         | LONG_SYM opt_binary
           { $$.set(MYSQL_TYPE_MEDIUM_BLOB); }
+        | JSON_SYM opt_binary
+          { $$.set(MYSQL_TYPE_BLOB); }
         ;
 
 spatial_type: