postgresql中,许多ddl语句支持if exists、if not exists。例如: postgres=# create table if not exists abce(); CREATE TABLE postgres=# drop table if exists abce; DROP
drop indexifexists"t_user_pkey";alter table"t_user"add constraint"t_user_pkey"primarykey("ID"); 根据已有表结构创建表 代码语言:javascript 代码运行次数:0 运行 AI代码解释 create tableifnot exists新表(like 旧表 including indexes including comments including defaults); 删除表 代码语言:javascript 代...
If you remove a column that does not exist, PostgreSQL will issue an error. To remove a column if it exists only, you can use the IF EXISTS option as follows: ALTER TABLE table_name DROP COLUMN IF EXISTS column_name; In this syntax, if you remove a column that does not exist, Postg...
COMMENT ON COLUMN public.t_user.update_time IS '更新时间'; -- 创建自增序列 alter sequence "t_user_ID_seq" restart with 1 increment by 1; -- 创建主键序列 drop index if exists "t_user_pkey"; alter table "t_user" add constraint "t_user_pkey" primary key ("ID"); 根据已有表结构创...
*去除缺省值: alter table [表名] alter column [字段名] drop default; 在表中插入数据: insert into 表名 ([字段名m],[字段名n],...) values ([列m的值],[列n的值],...); 修改表中的某行某列的数据: update [表名] set [目标字段名]=[目标值] where [该行特征]; 删除表中某...
五十八、DROP DATABASE DROP DATABASEDROP DATABASE — 移除一个数据库大纲DROP DATABASE [ IF EXISTS ] name [ [ WITH ] ( option [, ...] ) ] 其中 选项 可以是: FORCE描述DROP DATABASE移除一个数据库。它会移除该数据… 阅读全文 五十七、DROP CONVERSION ...
drop database [数据库名]; *重命名一个表: alter table [表名A] rename to [表名B]; *删除一个表: drop table [表名]; *在已有的表里添加字段: alter table [表名] add column [字段名] [类型]; *删除表中的字段: alter table [表名] drop column [字段名]; ...
drop table if exists bills ; create table bills ( id serial not null, goodsdesc text not null, beginunit text not null, begincity text not null, pubtime timestamp not null, amount float8 not null default 0, primary key (id) ); COMMENT ON TABLE bills is '运单记录'; COMMENT ...
要删除表的列,请在ALTER table语句中使用drop column子句,如下所示: ALTER TABLE res_partner rs DROP COLUMN rs.miss_schedule; 错误:“rs”行1处或附近的语法错误:ALTER TABLEres_partnerrs发布于 8 月前 ✅ 最佳回答: 请尝试不带别名的查询 ALTER TABLE res_partner DROP COLUMN miss_schedule; ...
DROP ROLE [ IF EXISTS ] _name_ [, ...]DROP RULE删除一个重写规则。DROP RULE name ON relation [ CASCADE | RESTRICT ]DROP SCHEMA删除一个模式。DROP SCHEMA name [, ...] [ CASCADE | RESTRICT ]DROP SEQUENCE删除一个序列。DROP SEQUENCE name [, ...] [ CASCADE | RESTRICT ]...