通俗易懂講解MySQL數據庫的增刪改查

CREATE?DATABASE?database_name

CREATE?TABLE?`user`?( ??`id`?int(11)?unsigned?NOT?NULL?AUTO_INCREMENT?COMMENT?'ID', ??PRIMARY?KEY?(`id`) )?ENGINE=MyISAM?DEFAULT?CHARSET=utf8;

DROP?TABLE?IF?EXISTS?`user`;

"ALTER?TABLE??`user`?ADD??`id`?int(11)?NOT?NULL?DEFAULT?'0'??COMMENT?'ID'" ALTER??TABLE??`user`??ADD??`name`?VARCHAR(?20??)??CHARACTER??SET?utf8?COLLATE?utf8_general_ci?NULL??DEFAULT? NULL??COMMENT??'姓名'

ALTER?TABLE??`user`?DROP?column?name

ALTER?TABLE?table_name?CHANGE?old_field_name?new_field_name?field_type;

alter?table?t1?change?b?b?bigint?not?null;?? alter?table?infos?change?list?list?tinyint?not?null?default?'0';

alter?table?t1?rename?t2; mysql>?alter?table?tablename?change?depno?depno?int(5)?not?null;?? mysql>?alter?table?tablename?add?index?索引名?(字段名1[，字段名2?…]);?? mysql>?alter?table?tablename?add?index?emp_name?(name);加主關鍵字的索引?? mysql>?alter?table?tablename?add?primary?key(id);加唯一限制條件的索引?? mysql>?alter?table?tablename?add?unique?emp_name2(cardnumber);刪除某個索引?? mysql>alter?table?tablename?drop?index?emp_name;修改表：

M('admin')->execute("ALTER?TABLE??`admin`?ADD??`id`?int(11)?NOT?NULL?DEFAULT?'0'??COMMENT?'ID'"); M('admin')->execute("ALTER?TABLE??`admin`?ADD??`name`?varchar(20)?DEFAULT?NULL??COMMENT?'姓名'");