1. CREATE OR REPLACE VIEW 按照"CREATE OR REPLACE VIEW" 关键字搜索,这部分代码在ATExecCmd函数(tablecmds.c文件)。可以看到它对应的命令类型叫AT_AddColumnToView,对应操作为调用ATExecAddColumn函数为视图新加列。 /* * ATExecCmd: dispatch a subcommand to appropriate execution routine */ static void AT...
create or replace view emp_details_view as select e.employee_id, e.job_id, e.manager_id, e.department_id, d.location_id, e.first_name, e.last_name, e.salary, e.commission_pct, d.department_name, j.job_title, e.hire_date from employees e join departments d on (e.department_id ...
虽然PostgreSQL提供了ALTER VIEW的语句,但怎么也不如直接放在CREATE VIEW里那样直观。 因此,建议脚本放弃Oracle风格的CREATE OR REPLACE VIEW形式,而改用MySQL风格的先DROP VIEW再CREATE VIEW的形式。不过,如果VIEW间存在层次引用关系,如视图A建立在视图B之上,则CREATE时必须先建B后建A,DROP时必须先删A再删B。当层次...
一、创建视图 create or replace viewvw_usersasselect * from users; 二、通过定义规则来更新视图 create rulevw_users_updas on update tovw_usersdo instead updateusers set user_email=New.user_email; updatevw_userssetuser_email='zhangsan@163.com'whereid=1; 注意,经过测试在9.5以上的版本可以直接使用...
SYSID uid | [ ENCRYPTED | UNENCRYPTED ] PASSWORD 'password' | CREATEDB | NOCREATEDB | CREATEUSER | NOCREATEUSER | IN GROUP group_name [, ...] | VALID UNTIL 'abs_time'CREATE VIEW定义一个视图。CREATE [ OR REPLACE ] VIEW name [ ( column_name [, ...] ) ] AS query...
--方式一:创建视图时带约束检查 postgres=# create or replace view employees_it as postgres-# select employee_id, postgres-# first_name, postgres-# last_name, postgres-# email, postgres-# phone_number, postgres-# hire_date, postgres-# job_id,manager_id, postgres-# department_id postgres-#...
CREATE OR REPLACE view_name AS query PostgreSQL 目前只支持追加视图定义中的字段,不支持减少字段或者修改字段的名称或顺序。例如,我们可以为视图 emp_details_view 增加一个字段 hire_date: create or replace view emp_details_view as select e.employee_id, e.job_id, e.manager_id, e.department_id, d...
CREATE [OR REPLACE] [TEMP | TEMPORARY] [RECURSIVE] VIEW name [(column_name[,...])] [WITH (view_option_name [=view_option_value][,...])] AS query [WITH [CASCADED | LOCAL] CHECK OPTION] 1. 创建普通视图 CREATE VIEW vw_employee AS SELECT empid,begindate,enddate,companyname,responsibi...
create table Anthor as select * from instructor where 1 = 2; 26.创建一个简单的视图 create view Stueent_No_Personal as select Student_ID, Last_Name, First_Name from Student; 27.PL/SQL块的结构 说明部分 执行部分 例外处理部分 例:
application_name is '应用名(客户端名)'; create or replace view pg_log as select * from pg_log_mon union all select * from pg_log_tue union all select * from pg_log_wed union all select * from pg_log_thu union all select * from pg_log_fri union all select * from pg_log_sat...