-- 創(chuàng)建表語句
ORACLE:
create table _table_name(
column1 varchar2(10) primary key,
column2 number(5) not null,
memo varchar2(100)
);
comment on column _table_name.column1
is '這是column1的注釋';
SQLSERVER:
create table _table_name(
column1 varchar(10) primary key,
column2 int not null,
memo varchar(100)
);
MYSQL:
create table `_table_name`
(
`column1` VARCHAR(32) primary key COMMENT '注釋',
`column2` VARCHAR(30) not null COMMENT '注釋',
PRIMARY KEY (`column1`) -- 主鍵定義也可放在此處
)ENGINE=InnoDB DEFAULT CHARSET=gbk;
-- 修改字段語句
ORACLE:
alter table _table_name add/modify column_name varchar2(505);
alter table _table_name drop column column_name;
SQLSERVER:
alter table _table_name add column_name VARCHAR(20);
alter table _table_name alter column column_name varchar(2000);
alter table _table_name drop column column_name;
MYSQL:
alter table _table_name add/modify column column_name varchar(2000);
alter table _table_name drop `column_name`;
-- 創(chuàng)建刪除索引語句,索引只能刪除重建,不能修改
ORACLE:
-- 主鍵索引
alter table _table_name add constraint index_name primary key (column_name) using index tablespace URMSPK;
-- 普通列索引
create index index_name$cl2 on _table_name (column1_name,column2_name DESC) tablespace URMSIDX;
-- 刪除索引
drop index index_name;
SQLSERVER:
-- 主鍵索引
Alter table _table_name add primary key(column_name);
alter table _table_name add constraint index_name primary key CLUSTERED (column_name)
WITH (
PAD_INDEX = OFF,
IGNORE_DUP_KEY = OFF,
STATISTICS_NORECOMPUTE = OFF,
ALLOW_ROW_LOCKS = ON,
ALLOW_PAGE_LOCKS = ON)
ON URMSPK
go
-- 普通列索引 ,非唯一索引需要去掉 UNIQUE NONCLUSTERED 關(guān)鍵字
CREATE UNIQUE NONCLUSTERED INDEX [index_name] ON [_table_name]
([ORGRANGE], [SHOWORDER] DESC)
WITH (
PAD_INDEX = OFF,
IGNORE_DUP_KEY = OFF,
DROP_EXISTING = OFF,
STATISTICS_NORECOMPUTE = OFF,
SORT_IN_TEMPDB = OFF,
ONLINE = OFF,
ALLOW_ROW_LOCKS = ON,
ALLOW_PAGE_LOCKS = ON)
ON [URMSIDX]
GO
-- 刪除索引
drop index _table_name.idxname;
MYSQL:
-- 普通索引
ALTER TABLE _table_name ADD INDEX index_name (APPID, CREATEDATE DESC);
-- 唯一索引
ALTER TABLE _table_name ADD UNIQUE index_name (column_list);
-- 主鍵索引
ALTER TABLE _table_name ADD PRIMARY KEY index_name (column_list);
-- 刪除索引
alter table _table_name drop index index_name;
-- 插入語句
ORACLE:
insert into _table_name (column_list) values ('value_list');
SQLSERVER:
insert into _table_name (column_list) values ('value_list');
MYSQL:
insert into UMFRAMESET (`column_list`) values ('value_list'),('value_list2');-- 可以插入多條記錄
-- 修改表名
ORACLE:
alter table leave rename to Leave01;
SQLSERVER:
EXEC sp_rename leave,leave01;
MYSQL:
alter table `leave` RENAME to `leave01`;
-- 刪除表語句
ORACLE:
drop table table_name;
SQLSERVER:
drop table table_name;
MYSQL:
drop table table_name
-- 刪除所有表的語句
SQLSERVER:
exec sp_msforeachtable 'drop table ?';
-- 修改列名
SQLSERVER:
EXEC sp_rename '表名.列名','新列名','column';
-- 刪除記錄
ORACLE:
delete (from) tablename where _column_name=?;
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