mysql数据库学习――3，表的创建，删除和变更_MySQL

表创建create table   mytbl(id   int    auto_increment  not null，name  char(10)  not null，birth  date     not null，wight  int，sex   enum('f','m'));指定数据库引擎的表创建create table     mytbl(id   int    auto_increment  not null，name  char(10)  not null，birth  date     not null，wight  int，sex   enum('f','m'))engine=memory;创建临时表create temporary  table   mytbl(id   int    auto_increment  not null，name  char(10)  not null，birth  date     not null，wight  int，sex   enum('f','m'));

复制数据表结构（也可以这样创建一个临时表作副本create  temporary table  tblnew  like   tblold）create table  tblnew  like   tblold同时复制数据insert into tblnew select * from tblold从查询结果创建表create  table  tblnew   select * from tblold

drop table tbl_namedrop table  tbl_name ,tbl2_namedrop table if exists  tbl_namedrop  temporary  table tbl_name

修改数据列的数据类型alter table mytbl modify  i   mediumint   unsignedalter  table  mytbl  chang i  i  mediumint   unsigned修改数据列的数据类型和字符集alter table mytbl modify  i   mediumint   character set  ucs2修改数据表的存储引擎alter table mytbl engine=engine_name

重命名数据表alter table tbl_name  rename to  new_tbl_namerename talbe  tbl_name to new_tbl_name重命名多个数据表 rename talbe  tbl_name to new_tbl_name，t1 to t2 ，t3  to t4移动数据表到另一个数据库alter table db1.tbl_name  rename to  db2.new_tbl_namerename talbe  db1.tbl_name to db2.new_tbl_name