--判断表格是否存在,不存在则返回结果为nullselectdistincttable_namefrominformation_schema.columnswheretable_schema='schemaName'andtable_name='tableName';--根据表格是否存在,进行删除操作droptableifexists'schemaName'.'tableName';--根据表格是否存在,进行创建操作createtableifnotexistsstudent ( idint, nameVARCH...
DROP TABLE postgres=# drop table if exists tb cascade; DROP TABLE postgres=# create table ta(id int primary key, name varchar); CREATE TABLE postgres=# create table tb(id int primary key, fid int , constraint fk_tb_fid foreign key(fid) references ta(id)); CREATE TABLE postgres=# inse...
–建表 DROP TABLE IF EXISTS "lianxi"."emp";--删除原有的emp表 -- 创建emp表 CREATE TABLE "lianxi"."emp" ( "empno" int4 NOT NULL, "ename" varchar(30) COLLATE "pg_catalog"."default", "job" varchar(30) COLLATE "pg_catalog"."default", "mgr" int4, "hiredate" date, "sal" numer...
1、建表语句 DROP TABLE IF EXISTS "public"."json_param"; CREATE TABLE "public"."json_param" ( "id" int4 NOT NULL, "json" text COLLATE "pg_catalog"."default" ); INSERT INTO "public"."json_param" VALUES (1, '{"name":"xinglei","age":20,"grade":{"math":80,"english":90},"...
create table if not exists 新表 (like 旧表 including indexes including comments including defaults); 删除表 drop table if exists "t_template" cascade; 查询注释 SELECT a.attname as "字段名", col_description(a.attrelid,a.attnum) as "注释", ...
# 创建表CREATETABLECOMPANY(IDINTPRIMARYKEYNOTNULL,NAMETEXTNOTNULL,AGEINTNOTNULL,ADDRESSCHAR(50),SALARYREAL);# 删除表droptableifexistscompany;# 列举表,相当于mysql的show tables\d# 查看表结构,相当于desc tblname,show columns from tbname\d company# 查看索引\di ...
我在SQL dump中有一个问题,那就是CREATE TABLE IF EXISTS。这在Postgres中是无效的。我无法从该转储中删除此行,因为它的大小很大(5 5GB)。 我在Google Cloud中完成了所有这些工作。如果有任何方法可以从Google SQL迁移到Postgres,那对我来说也是可行的。 浏览6提问于2019-04-18得票数 0 2回答 pg_restore...
ALTERTABLEuser_tbl RENAME COLUMN signup_date TO signup; --删除栏位 ALTERTABLEuser_tblDROPCOLUMN email; --表格更名 ALTERTABLEuser_tbl RENAME TO backup_tbl; --删除表格 DROPTABLEIF EXISTS backup_tbl; 1. 2. 3. 4. 5. 6. 7. 8.
1 ALTER TABLE "public"."tableName" 2 ADD PRIMARY KEY ("id"); 6.强制加自增(这个有借鉴别人写的) 1 ALTER TABLE tablename ALTER COLUMN id SET DEFAULT null;2 DROP SEQUENCE IF EXISTS tablename_id_seq;3 -- 这里的 id_max 即 id 目前的最大值,可通过 “SELECT MAX(id) FROM tablename” ...
DROP TABLE IF EXISTS"public"."ad_arrow";CREATE TABLE"public"."ad_arrow"("arr_id"int8 PRIMARY KEY NOTNULL,"arr_direct"varchar(20)NOTNULLDEFAULT'0',"confidence"varchar(1024)COLLATE"pg_catalog"."default","upd_stat"varchar(512)COLLATE"pg_catalog"."default","cur_task_id"int8 NOTNULL,"ti...