mariadb/mysql-test/r/have_cp866.require

Collation	Charset	Id	Default	Compiled	Sortlen
cp866_general_ci	cp866	36	Yes		0
Patch for the following bugs: - BUG#11986: Stored routines and triggers can fail if the code has a non-ascii symbol - BUG#16291: mysqldump corrupts string-constants with non-ascii-chars - BUG#19443: INFORMATION_SCHEMA does not support charsets properly - BUG#21249: Character set of SP-var can be ignored - BUG#25212: Character set of string constant is ignored (stored routines) - BUG#25221: Character set of string constant is ignored (triggers) There were a few general problems that caused these bugs: 1. Character set information of the original (definition) query for views, triggers, stored routines and events was lost. 2. mysqldump output query in client character set, which can be inappropriate to encode definition-query. 3. INFORMATION_SCHEMA used strings with mixed encodings to display object definition; 1. No query-definition-character set. In order to compile query into execution code, some extra data (such as environment variables or the database character set) is used. The problem here was that this context was not preserved. So, on the next load it can differ from the original one, thus the result will be different. The context contains the following data: - client character set; - connection collation (character set and collation); - collation of the owner database; The fix is to store this context and use it each time we parse (compile) and execute the object (stored routine, trigger, ...). 2. Wrong mysqldump-output. The original query can contain several encodings (by means of character set introducers). The problem here was that we tried to convert original query to the mysqldump-client character set. Moreover, we stored queries in different character sets for different objects (views, for one, used UTF8, triggers used original character set). The solution is - to store definition queries in the original character set; - to change SHOW CREATE statement to output definition query in the binary character set (i.e. without any conversion); - introduce SHOW CREATE TRIGGER statement; - to dump special statements to switch the context to the original one before dumping and restore it afterwards. Note, in order to preserve the database collation at the creation time, additional ALTER DATABASE might be used (to temporary switch the database collation back to the original value). In this case, ALTER DATABASE privilege will be required. This is a backward-incompatible change. 3. INFORMATION_SCHEMA showed non-UTF8 strings The fix is to generate UTF8-query during the parsing, store it in the object and show it in the INFORMATION_SCHEMA. Basically, the idea is to create a copy of the original query convert it to UTF8. Character set introducers are removed and all text literals are converted to UTF8. This UTF8 query is intended to provide user-readable output. It must not be used to recreate the object. Specialized SHOW CREATE statements should be used for this. The reason for this limitation is the following: the original query can contain symbols from several character sets (by means of character set introducers). Example: - original query: CREATE VIEW v1 AS SELECT _cp1251 'Hello' AS c1; - UTF8 query (for INFORMATION_SCHEMA): CREATE VIEW v1 AS SELECT 'Hello' AS c1; 2007-06-28 19:34:54 +02:00			`Collation Charset Id Default Compiled Sortlen`
			`cp866_general_ci cp866 36 Yes 0`