#PostgreSQL# select * from pg_tables; 表明有大写要双引号包含。 select * from "Users";
select pg_size_pretty(pg_total_relation_size('table_name')) as size; 5、查看表中索引大小 select pg_size_pretty(pg_indexes_size('product')); 6、获取各个表中的数据记录数 select relname as TABLE_NAME, reltuples as rowCounts from pg_class where relkind = 'r' order by rowCounts desc 7...
SELECT retrieves data from a table or view.Serving as an overlaid filter for a database table, SELECT using SQL keywords retrieves required data from data tables.Using SE
Now I have a database database table with an owner user, yet I receive ERROR: permission denied for table alert whenever I try to select from this table: database=# SET ROLE user; SET database=> select * from pg_tables where tablename = 'alert'; schemaname | tablename | tableo...
但特别需要注意,该强制删除用户因为是级联删除,因此,很大概率会把依赖的schema和table都删除,所以此方式强制删除用户需要提前备份,防止发生不测。 test1=# \du+List of rolesRole name | Attributes | Member of | Description---+---+---+---drmc | | {} |pg1 | Superuser, Create role, Create DB,...
前言在使用数据库的过程中,我们最常用到还是查询语句,即select* from tablename, 这篇博客就通过具体的实例说明一下select语句的用法。创建数据库及数据表为了统一下面的查询语句,我这里给出语句,只需要复制然后在你的数据库中执行,就可以创建和笔者一样的数据库环境create database mydb;//创建数据库 use mydb;...
delete from student where name='小梁' ●删除字段 alter table 表名 drop column 列名 ; 比如 alter table student drop column sex ; ●更新记录 update student set name='大梁' where id=3 ●新增或更新 --如果id冲突就更新 insert into student(id, name,class_id) ...
Summary: in this tutorial, you will learn how to use the PostgreSQL SELECT INTO statement to create a new table from the result set of a query. If you want to select data into variables, check out the PL/pgSQL SELECT INTO statement. Introduction to PostgreSQL SELECT INTO statement The Pos...
SHOW TABLES[ LIKE pattern ] SHOW TABLES FROM 表名-- 查看表机构 SHOW CREATE TABLE 表名 (信息更详细) DESC 表名 / DESCRIBE 表名 / EXPLAIN 表名 / SHOW COLUMNS FROM 表名 [LIKE PATTERN ] SHOW TABLE STATUS [FROM db_name] [LIKE pattern ]-- 修改表 -- 修改表本身的选项 ALTER TABLE 表名...
Insert into a Table from Raw SQL Selectval rawSql: DBIO[Vector[(String, String)]] = sql"SELECT id, name FROM SomeTable".as[(String, String)] val myTable :TableQuery[MyClass] // with columns id (String), name(String) and some other columns Is there a way to use forceInsert ...