SQL>createtableemp1asselect*fromempwhere1=2; SQL>insertintoemp1select*from emp;conventional传统方式数据 SQL> insert /*+ APPEND */ into emp1 select * from emp; 直接方式数据,必须 commit后才能查看数据 创建表插入数据 代码语言:javascript
SELECT子句是查询语句中必不可少的部分,由SELECT关键字及至少一个标识要检索列的表达式构成,多个表达式之间以英文逗号分隔;支持的表达式包括但不限于如下情况: 字面量,如 SELECT 1, "hello" 所有列的简写,如 SELECT * FROM ... 限定表名或表别名的列,如 SELECT t1.name, t2.* FROM t1, table2 as t2 ...
FROMtablename1, tablename2WHEREcondition 常见的子查询: SELECT*FROMtablename1WHEREcolname1 [NOT]IN(SELECTcolname2FROMtablename2) SELECT*FROMtablename1WHEREcolname1=|!=(SELECTcolname2FROMtablename2) SELECT*FROMtablename1WHERE[NOT]EXISTS(SELECT*FROMtablename2WHEREtablename1.colname1=tablename2.col...
SQL: select a.title,a.username,b.adddate from table a,(select max(adddate) adddate from table where table.title=a.title) b 说明:外连接查询(表名1:a 表名2:b) SQL: select a.a, a.b, a.c, b.c, b.d, b.f from a LEFT OUT JOIN b ON a.a = b.c 说明:日程安排提前五分钟提...
USE TemporalProductInventory; GO BEGIN --If table is system-versioned, SYSTEM_VERSIONING must be set to OFF first IF ((SELECT temporal_type FROM SYS.TABLES WHERE object_id = OBJECT_ID('dbo.ProductInventory', 'U')) = 2) BEGIN ALTER TABLE [dbo].[ProductInventory] SET (SYSTEM_VERSIONING...
USE TestDatabase; GO TRUNCATE TABLE myTestSkipField; INSERT INTO dbo.myTestSkipField SELECT * FROM OPENROWSET ( BULK 'D:\BCP\myTestSkipField.bcp', FORMATFILE = 'D:\BCP\myTestSkipField.fmt' ) AS t1; GO -- review results SELECT * FROM TestDatabase.dbo.myTestSkipField; 使用OPENROWSET(BUL...
select P.FirstName AS FN,P.MiddleName AS MN,P.LastName AS LN from Person.Person AS P 4.select FirstName,MiddleName from (select FirstName,MiddleName,LastName from Person.Person) AS PersonName PersonName相当于是一个虚拟表,把这个虚拟表当成是table source 其中()不能删除,删除后会出现语法错误...
SELECT * FROM RECORD WHERE CARD_NO LIKE ‘5378%’ SELECT member_number, first_name, last_name FROM members WHERE DATEDIFF(yy,datofbirth,GETDATE()) > 21 应改为: SELECT member_number, first_name, last_name FROM members WHERE dateofbirth < DATEADD(yy,-21,GETDATE()) ...
有关BULK INSERT 语句、INSERT ... SELECT * FROM OPENROWSET(BULK...)语句和bcp命令的比较,请参阅批量导入和导出数据。 有关准备数据进行批量导入的信息,请参阅准备数据进行批量导出或导入。 BULK INSERT 语句可在用户定义的事务内执行,以便将数据导入到表或视图中。 或者,为了将多个匹配项用于大容量导入数据,事...
表Table--存储的基本单元关系型数据库中表是一个二维结构由行( Row )和列( Record )组成 视图View--虚拟的表,视图对应一条Select 语句,查询得到的结果集被赋予一个名字即视图的名字 索引Index--用来在数据库中加速表查询的数据库对象 序列Sequence--用来生成唯一数字值的数据库对象,值由Oracle 按递增或递减顺序...