Drop Down MenusCSS Drop Down MenuPure CSS Dropdown Menu

Postgresql ERROR: relation "pg_catalog" does not exist because pg_catalog is a schema

-
I couldn't find anything in the postgresql manual as how to view its
 content. SELECT does not seem to work.
       
 What's the exact command and error message?
netilla=#  \dn
        List of schemas
        Name        |  Owner
 --------------------+----------
 information_schema | postgres
 pg_catalog         | postgres
 pg_toast           | postgres
 public             | postgres
 (4 rows)

 netilla=# select * from pg_catalog;
 ERROR:  relation "pg_catalog" does not exist
     
   
That would be because pg_catalog is a schema; you can't select from it.
If you want to see what's in there, use \dS.

Comments

Post a Comment

Popular posts from this blog

How to find the server is whether standby (slave) or primary(master) in Postgresql replication ?

-
Method 1 You can check the mode of the server using "pg_controldata". [pgsql@test~]$ pg_controldata /usr/local/pgsql/data84/ Database cluster state: in archive recovery --> This is Standby Database Database cluster state: in production --> This is Production Database [Master] Method 2 You can use pg_is_in_recovery() which returns True if recovery is still in progress(so the server is running in standby mode or slave) postgres=# select pg_is_in_recovery(); pg_is_in_recovery ------------------- t (1 row) If Return    false   so the server is running in primary mode or master postgres=# select pg_is_in_recovery(); pg_is_in_recovery ------------------- f (1 row)
Read more

How to Get Table Size, Database Size, Indexes Size, schema Size, Tablespace Size, column Size in PostgreSQL Database

-
In this post, I am sharing few important function for finding the size of database, table and index in PostgreSQL. Finding object size in postgresql database is very important and common. Is it very useful to know the exact size occupied by the object at the tablespace. The object size in the following scripts is in GB. The scripts have been formatted to work very easily with PUTTY SQL Editor. 1. Checking table size excluding table dependency: SELECT pg_size_pretty(pg_relation_size('mhrordhu_shk.mut_kharedi_audit')); pg_size_pretty ---------------- 238 MB (1 row) 2. Checking table size including table dependency: SELECT pg_size_pretty(pg_total_relation_size('mhrordhu_shk.mut_kharedi_audit')); pg_size_pretty ---------------- 268 MB (1 row) 3. Finding individual postgresql database size SELECT pg_size_pretty(pg_database_size('db_name')); 4. Finding individual table size for postgresql database -including dependency index: SELECT pg_size_pretty(pg_total_rel
Read more

How to Return a Result Set from a PostgreSQL Stored Procedure

-
Image
Both stored procedures and user-defined functions are created with CREATE FUNCTION statement in PostgreSQL. To return one or more result sets (cursors in terms of PostgreSQL), you have to use  refcursor  return type. Quick Example : -- Procedure that returns a single result set (cursor) CREATE OR REPLACE FUNCTION show_cities ( ) RETURNS refcursor AS $$ DECLARE ref refcursor; -- Declare a cursor variable BEGIN OPEN ref FOR SELECT city , state FROM cities; -- Open a cursor RETURN ref; -- Return the cursor to the caller END ; $$ LANGUAGE plpgsql; Overview : Return Multiple Result Sets Cursor Lifetime Until the  end  of transaction Auto-commit Must be  off Transaction must be active so the caller can see a result set Important Note : The cursor remains open until the end of transaction, and since PostgreSQL works
Read more

7 Steps to configure BDR replication in postgresql

-
Image
 The  BDR  (Bi-Directional Replication) project adds multi-master replication to PostgreSQL 9.4.  Postgres-BDR has a lower impact on the masters(s) than trigger-based replication solutions. There is no write-amplification, as it does not require triggers to write to queue tables in order to replicate writes.   Here We are using  postgres version 9.4.12 and bdr version 1.0.2. for configuring  multi master replication . Simply Following 7 steps you can configure the multi master replication in postgresql. To download the bdr in below link. .   https://github.com/2ndQuadrant/bdr/archive/bdr-pg/REL9_4_12-1.tar.gz $ tar -xzvf REL9_4_12-1.tar.gz $ wget https://github.com/2ndQuadrant/bdr/archive/bdr-plugin/1.0.2.tar.gz $ tar -xzvf 1.0.2.tar.gz 1. To install BDR. $ cd ~/bdr-bdr-pg-REL9_4_12-1 $ ./configure --prefix=/usr/lib/postgresql/9.4 --enable-debug --with-openssl $ make -j4 -s install-world $ cd ~/bdr-bdr-plugin-1.0.2 $ PATH=/usr/lib/postgresql/9.4/bin:"$PATH" ./c
Read more

PostgreSQL Pgbadger Installation On Linux

-
Image
PgBadger is a tool that analyzes PostgreSQL log files and generates reports on execution of SQL and server operation. Statistical reports analyzed from a number of perspectives can be useful not only for grasping the usual database operation but also as a hint for performance improvement. The report output by pgBadger has the following features. Graph output in HTML format Many statistical objects Daily, Weekly unit creation possible 1.Graph output in HTML format Many of the analysis results can be displayed in graph form by outputting the report in HTML format (output in text format or JSON format is also possible). By analyzing the log information graphed, it is much more prospective for people to see than the raw log data. So, if you do not need to handle it with another tool separately, we recommend report output in HTML format. 2.Many statistical objects A lot of data useful for database performance analysis is output in the report as shown below. Qu
Read more