PostgreSQL index types have basically divided into six types, i.e., B-tree, hash, GIN, BRIN, SP-GIST, and GiST index, each of the index types has different storage structures and algorithm to retrieve data from
视图On views, triggers can be defined to execute instead of INSERT, UPDATE, or DELETE operations.INSTEAD OF triggers are fired once for each row that needs to be modified in the view.It is the responsibility of the trigger's function to perform the necessary modifications to the underlying ...
variables show help on special variables \h [NAME] help on syntax of SQL commands, * for all commandsQuery Buffer \e [FILE] [LINE] edit the query buffer (or file) with external editor \ef [FUNCNAME [LINE]] edit function definition with external editor...Informational (o...
PostgreSQL index types have basically divided into six types, i.e.,B-tree, hash, GIN, BRIN, SP-GIST, and GiST index, each of the index types has different storage structures and algorithm to retrieve data from the query. PostgreSQL 的索引类型基本上分为六种,即B 树索引、哈希索引、GIN 索引...
MySQL –compare PostgreSQL with MySQL in terms of functionalities. Advanced PostgreSQL Tutorial This advanced PostgreSQL tutorial covers the advanced concepts including stored procedures, indexes, views, triggers, and database administrations. PostgreSQL PL/pgSQL This PostgreSQL stored procedures section ...
PostgreSQL index is slowing operations on insert and update statement, we can create an update and delete index with no loss of data. PostgreSQL 索引会减慢插入和更新语句的操作速度,我们可以在不丢失数据的情况下创建更新和删除索引。 Below are the types of index available in PostgreSQL: ...
materialized views, composite types, and TOAST tables; see relkind. Below, when we mean all of these kinds of objects we speak of “relations”. Not all columns are meaningful for all relation types. ben发布于博客园 The catalog pg_description:官文 ...
system_views.sql 系统视图SQL脚本 以及配置文件模板(包括主配置文件的模板和连接权限hba模板) 4, data目录 此目录通常我们也可以称之为数据文件目录。由于Linux的设计理念是万物皆为文件,因此,逻辑上的所有概念都可以物化为文件 此目录只有初始化数据库后才会生成出现,该目录下存放的是几个主要配置文件和数据库的物理...
\dT[S+] [PATTERN] list data types \du[+] [PATTERN] list roles \dv[S+] [PATTERN] list views \dE[S+] [PATTERN] list foreign tables \dx[+] [PATTERN] list extensions \l[+] list all databases \sf[+] FUNCNAME show a function's definition ...
Also, information about the actual data types of columns and expression results is added to the query tree. PartIV. The PostgreSQL Rule System PostgreSQL supports a powerful rule system for the specification of views and ambiguous view updates. Originally the PostgreSQL rule system consisted of two...