1 SELECT TABLE_NAME '表名',TABLE_SCHEMA '數據庫名',ORDINAL_POSITION '順序',COLUMN_NAME '字段',DATA_TYPE '類型' 2 ,CHARACTER_OCTET_LENGTH '字節長',IF(COLUMN_KEY='PRI',"√","") '主鍵',IF(EXTRA='auto_increment',"√","") '自增長' 3 ,IF(IS_NULLABLE='YES',"√","") '空',CHARACTER_SET_NAME '編碼',COLUMN_DEFAULT '默認值',COLUMN_COMMENT '說明' 4 FROM information_schema.COLUMNS WHERE TABLE_SCHEMA='dzbbs' AND COLUMN_NAME='username'
#是查詢數據庫名為dzbbsdb的數據庫中所有包含username列名的表信息。