In PostgreSQL, a primary key constraint uniquely identifies rows. One or more columns can be defined as a primary key in a table. Primary key is a combination of NOT NULL constraint and UNIQUE constraint, meaning, the column or group of columns that are defined as the primary key enforce ...
AI代码解释 CREATETABLEpublic.student(id int4NOTNULL,addressvarchar(255)NULL,emailvarchar(255)NULL,"name"varchar(255)NULL,CONSTRAINTstudent_pkeyPRIMARYKEY(id)); 接下来有两个事务执行批量插入操作,事务1先插入student3,再插入student4,如下: 代码语言:javascript 代码运行次数:0 运行 AI代码解释 begin transac...
coalesce(E'\nPARTITION BY '||pg_get_partkeydef(tabdef.oid), '') ) as table_create_sql FROM tabdef $$; 代码语言:txt AI代码解释 效果: test=# select tabledef('public','autovacuum_monitoring'); tabledef --- CREATE TABLE public.autovacuum_monitoring ( + id integer NOT NULL DEFAULT nex...
"select tablename from pg_tables where schemaname='public'" —— 得到所有用户自定义表的名字(这里"tablename"字段是表的名字,"schemaname"是schema的名字。用户自定义的表,如果未经特殊处理,默认都是放在名为public的schema下) General \copyright show PostgreSQL usage and distribution terms \g [FILE] or ...
playboy=>\d test;//相当于mysql的,mysql>desctest;Table"public.test"Column|Type|Modifiers---+---+---id|integer|notnullname|charactervarying(32)|Indexes: "playboy_id_pk"PRIMARYKEY, btree (id) playboy=>selectpg_relation_size('test');//查看表...
表范围的约束可以是UNIQUE,PRIMARY KEY,CHECK或REFERENCES。 如何在PostgreSQL中创建表 我们将创建一个名为“pg_equipment”的表,它定义了各种游乐场设备。输入以下表定义: CREATE TABLE pg_equipment ( equip_id serial PRIMARY KEY, type varchar (50) NOT NULL, color varchar (25) NOT NULL, location varchar...
create table db_test(id int primary key, name varchar(50), age int); postgres=# select * from pg_class where relname ='db_test'; oid | relname | relnamespace | reltype | reloftype | relowner | relam | relfilenode | reltablespace | relpages | reltuples | relallvisible | reltoa...
CREATE TABLE employees ( id SERIAL PRIMARY KEY, -- SERIAL自动生成唯一标识符 name TEXT NOT NULL, -- TEXT类型存储长文本(无长度限制) salary NUMERIC(10, 2), -- 精确数值类型(总长度10,小数位2) hire_date DATE DEFAULT CURRENT_DATE -- 默认值为当前日期 ...
-- Drop the table if it already exists DROP TABLE IF EXISTS customers; -- Create a new table called 'customers' CREATE TABLE customers( customer_id SERIAL PRIMARY KEY, name VARCHAR (50) NOT NULL, location VARCHAR (50) NOT NULL, email VARCHAR (50) NOT NULL ); 插入列 將下列程式碼片段...
postgres=# CREATE TABLE data(id serial primary key, data text);CREATE TABLE 3)检测prepare事务和commit事务的解码输出内容 postgres=# BEGIN;postgres=*# INSERT INTO data(data) VALUES('5');postgres=*# PREPARE TRANSACTION 'test_prepared1';postgres=# SELECT * FROM pg_logical_slot_get_changes('reg...