[[DEFAULT] COLLATE collation_name ] ALTER DATABASE db_name [[DEFAULT] CHARACTER SET charset_name ] [[DEFAULT] COLLATE collation_name ] 

The keyword SCHEMA  can be used instead of DATABASE . 

The CHARACTER SET  and COLLATE  clauses make it possible to create databases with different character sets and collations on the same MySQL server. 

Database options are stored in the data dictionary and can be examined by checking the INFORMATION_SCHEMA.SCHEMATA  table. 

Example: 

CREATE DATABASE db_name  CHARACTER SET latin1 COLLATE latin1_swedish_ci; 

MySQL chooses the database character set and database collation in the following manner: 

•If both CHARACTER SET charset_name  and COLLATE collation_name  are specified, character set charset_name  and collation collation_name  are used. 

•If CHARACTER SET charset_name  is specified without COLLATE , character set charset_name and its default collation are used. To see the default collation for each character set, use the SHOW CHARACTER SET  statement or query the INFORMATION_SCHEMA CHARACTER_SETS  table. 

•If COLLATE collation_name  is specified without CHARACTER SET , the character set associated with collation_name  and collation collation_name  are used. 

•Otherwise (neither CHARACTER SET  nor COLLATE  is specified), the server character set and server collation are used. 

The character set and collation for the default database can be determined from the values of the character_set_database  and collation_database  system variables. The server sets these variables whenever the default database changes. If there is no default database, the variables have the same value as the corresponding server-level system variables, character_set_server  and collation_server . 

To see the default character set and collation for a given database, use these statements: 

USE db_name ; SELECT @@character_set_database, @@collation_database; 

Alternatively, to display the values without changing the default database: 

SELECT DEFAULT_CHARACTER_SET_NAME, DEFAULT_COLLATION_NAME FROM INFORMATION_SCHEMA.SCHEMATA WHERE SCHEMA_NAME = ’ db_name ’; 

The database character set and collation affect these aspects of server operation: 

•For CREATE TABLE  statements, the database character set and collation are used as default values for table definitions if the table character set and collation are not specified. To override this, provide explicit CHARACTER SET  and COLLATE  table options. 

•For LOAD DATA  statements that include no CHARACTER SET  clause, the server uses the character set indicated by the character_set_database  system variable to interpret the information in the file. To override this, provide an explicit CHARACTER SET  clause. 

•For stored routines (procedures and functions), the database character set and collation in effect at routine creation time are used as the character set and collation of character data parameters for 

