In PostgreSQL, a new table can be created via theSELECTcommand; for this purpose, theCREATE TABLEstatement is used along with an AS clause followed by aSELECTstatement. The newly created table will have the same table structure (e.g., column names, data types, etc.) as the columns in th...
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...
In PostgreSQL, theSELECT INTOstatement performs various functionalities in one go. The stated command creates a new table, copies data from the original table, and pastes it into the newly created table. The newly created table will have the same structure as the original/selected table. Using ...
postgresql做为一个比较复杂的关系型的重型数据库,不管是安装部署,还是后期的运行维护,都还是有比较多的细节问题需要引起关注。 例如,用户权限的合理分配,那么,什么是权限的合理分配呢? 自然是权限的最小化原则,也就是说每个用户能够完成其权限范围内的工作,而不会由于黑客攻击,漏洞等原因造成安全方面的危险。 在写...
For more information, seeINSERTin theOracle documentation. PostgreSQL usage PostgreSQLINSERT FROM SELECTsyntax is mostly compatible with the Oracle syntax, except for a few Oracle-only features such as the conditional_insert_clause (ALL|FIRST|ELSE). Also, PostgreSQL doesn’t support ...
Also, if you’re interested in the full syntax, you can find the references for several database vendors here: SQL Server Oracle MySQL PostgreSQL Let’s take a look at each of the keywords within the SELECT statement. SELECT The SELECT clause of the SELECT statement refers to the first lin...
This tutorial works for PostgreSQL anywhere. Postgres on Neon provisions in 1 second. Get the free plan here. Summary: in this tutorial, you will learn how to use the PL/pgSQL select into statement to select data from the database and assign it to a variable. Introduction to PL/pgSQL ...
在PostgreSQL 中,DISTINCT 关键字与 SELECT 语句一起使用,用于去除重复记录,只获取唯一的记录。 我们平时在操作数据时,有可能出现一种情况,在一个表中有多个重复的记录,当提取这样的记录时,DISTINCT 关键字就显得特别有意义,它只获取唯一一次记录,而不是获取重复记录。
子查询或称为内部查询、嵌套查询,指的是在 PostgreSQL 查询中的 WHERE 子句中嵌入查询语句。一个 SELECT 语句的查询结果能够作为另一个语句的输入值。...以下是子查询必须遵循的几个规则:子查询必须用括号括起来。子查询在 SELECT 子句中只能有一个列,除非在主查询中
PostgreSQL 的审计还是要借助PostgreSQL的扩展pgaudit 来进行。...与大部分的audit 的方式不同pg_audit记录在标准的PostgreSQL日志中。...说明这个东西还是蛮好用的。...OBJECT_NAME - 操作的OBJECT 类型的名字,例如表名,存储过程名等等 STATEMENT - 执行的语句 PARAMETER - 相关的参数 此时有人可能提出,这个设计的...