关键字

关键字是在 StackQL 语法中具有特定含义的保留字。关键字可以用任意大小写形式（大写、小写或混合）输入，按照惯例，所有示例中的关键字均为大写。StackQL 中的关键字包括：

ADD, AND, AS, ASC, BETWEEN, BINARY, BY, CASE, COLLATE, CONVERT, CREATE, CROSS, CURRENT_DATE, CURRENT_TIME, CURRENT_TIMESTAMP, DATABASE, DATABASES, DELETE, DESC, DESCRIBE, DISTINCT, DIV, DROP, ELSE, END, ESCAPE, EXEC, EXISTS, EXPLAIN, FALSE, FOR, FROM, GROUP, HAVING, IF, IGNORE, IN, INDEX, INNER, INSERT, INTERVAL, INTO, IS, JOIN, LEFT, LIKE, LIMIT, LOCALTIME, LOCALTIMESTAMP, LOCK, MOD, NATURAL, NEXT, NOT, NULL, OFF, ON, OR, ORDER, OUTER, OVER, RECURSIVE, REGEXP, REPLACE, RETURNING, RIGHT, SCHEMA, SELECT, SEPARATOR, SESSION, SET, SHOW, SUBSTR, SUBSTRING, TABLE, THEN, TIMESTAMPADD, TIMESTAMPDIFF, TO, TRUE, UNION, UNSET, UPDATE, USE, USING, UTC_DATE, UTC_TIME, UTC_TIMESTAMP, VALUES, WHEN, WHERE, XOR