parser: add support for ALTER DATABASE syntax
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PTAL @kennytm , thank you! |
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Thank you very much @kennytm |
| @@ -3237,7 +3270,7 @@ Identifier: | |||
| identifier | UnReservedKeyword | NotKeywordToken | TiDBKeyword | |||
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| UnReservedKeyword: | |||
| "ACTION" | "ASCII" | "AUTO_INCREMENT" | "AFTER" | "ALWAYS" | "AVG" | "BEGIN" | "BIT" | "BOOL" | "BOOLEAN" | "BTREE" | "BYTE" | "CLEANUP" | "CHARSET" | |||
| "ACTION" | "ASCII" | "AUTO_INCREMENT" | "AFTER" | "ALWAYS" | "AVG" | "BEGIN" | "BIT" | "BOOL" | "BOOLEAN" | "BTREE" | "BYTE" | "CLEANUP" | "CHARSET" %prec charsetKwd | |||
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Do we need to care about "CHARACTER" "SET"? I am not very clear about this.
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Do we need to care about
"CHARACTER" "SET"? I am not very clear about this.
@zimulala The reason is CHARACTER is a reserved token but CHARSET is unreserved. For example,
mysql> create database charset;
Query OK, 1 row affected
mysql> create database character;
(1064, "You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'character' at line 1")
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why we use
%prechere?
@zimulala @winkyao the reason is CHARSET is an unreserved keyword. There's a shift/reduce conflict when parsing AlterDatabseStmt CHARSET, YACC need to decide if charset is treated as CHARACTER SET keyword, or the database name.
BTW, this precedence leads to the following parsing result:
mysql> alter database charset=utf8;
(1064, "You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '=utf8' at line 1")
mysql> alter database character set=utf8;
Query OK, 1 row affected
And it is consistent with MySQL parser.
What problem does this PR solve?
Add support for
ALTER DATABASEsyntaxRelated issue: pingcap/tidb#4641
What is changed and how it works?
Modified parser.y
Check List
Tests
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