显示数据库Show Databases
SHOW [DATABASES | SCHEMAS] [LIKE 'pattern']
返回所有数据库。Return all databases. SHOW SCHEMAS 是 SHOW DATABASES的同义词。SHOW SCHEMAS is a synonym for SHOW DATABASES.
LIKE 'pattern'
要匹配的数据库名称。Which database names to match. 在 pattern 中，* 匹配任意数量的字符。In pattern, * matches any number of characters.