MySQL中插入数据列到特定列
MySQL中插入数据列的命令alter table tablename add column_definition,如果不指定数据列的位置的时候,插入的列一般在最后,如
MySQL中插入数据列的命令
alter table tablename add column_definition,如果不指定数据列的位置的时候,插入的列一般在最后,如果要插入到特定的列后则:
alter table tablename ADD [COLUMN] column_definition [FIRST | AFTER col_name ],比如现在数据列有11列现在想把12列加在第四列后面,则:
alter tabel 表名1 Add 数据列12 varchar(100)after 数据列4。
给表重新命名,把旧名oldname重新命名为newname
ALTER TABLE oldname RENAME newname;
复制mysql表有来种方法:
1,复制整个表:
create table 新表 select * from 旧表;
2.只复制表结构:
create table 新表 select * from 旧表 where 11;

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