Drop Down MenusCSS Drop Down MenuPure CSS Dropdown Menu

PostgresqlDBA interview questions and answers

-

Questions :I have three  tables which contains around 20millions of records. I am planning to update these three tables for all records. Could you suggest me best approaches to meet this, please?
Ans:
1.I think disable index before update ? And autovacuum off,arhvive off if possible.
2.Increase the check point time out
Increase shared buffer or wall beffer if archive enable.
3.Check any parallel option is there.

Comments

Post a Comment

Popular posts from this blog

PostgreSQL pgBadger

-
pgBadger is a PostgreSQL log analyzer built for speed with fully reports from your PostgreSQL log file. It's a single and small Perl script that outperforms any other PostgreSQL log analyzer.It is written in pure Perl and uses a JavaScript library (flotr2) to draw graphs so that you don't need to install any additional Perl modules or other packages. Furthermore, this library gives us more features such as zooming. pgBadger also uses the Bootstrap JavaScript library and the FontAwesome webfont for better design. Everything is embedded.pgBadger is able to autodetect your log file format (syslog, stderr or csvlog). It is designed to parse huge log files as well as gzip compressed files. See a complete list of features below. Supported compressed format are gzip, bzip2 and xz. For the xz format you must have an xz version upper than 5.05 that supports the --robot option.All charts are zoomable and can be saved as PNG images.You can also limit pgBadger to only report errors or rem…
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. Queries (total number of executions, maxi…
Read more

How to configure Replication Manager (repmgr) ?

-
`repmgr` is a suite of open-source tools to manage replication and failover within a cluster of PostgreSQL servers. It enhances PostgreSQL's built-in replication capabilities with utilities to set up standby servers, monitor replication, and perform administrative tasks such as failover or switchover operations. The current `repmgr` version (3.3) supports all PostgreSQL versions from 9.3 to 9.6. Overview The repmgr suite provides two main tools:1.repmgr - a command-line tool used to perform administrative tasks such as: - setting up standby servers - promoting a standby server to master - switching over master and standby servers - displaying the status of servers in the replication cluster 2.repmgrd is a daemon which actively monitors servers in a replication cluster and performs the following tasks: - monitoring and recording replication performance - performing failover by detecting failure of the master and promoting the most suitabl…
Read more

ORA-01261: Parameter db_recovery_file_dest destination string cannot be translated ORA-01262: Stat failed on a file destination directory Linux-x86_64 Error: 2: No such file or directory

-
While I start my database with my initialization parameter it fails with oracle error
Solution :- su oracle
run environment variable
sqlplus / as sysdba

SQL>create pfile from spfile; Then remove or comment below line in pfile db_recovery_file_dest Save and exit su oracle
run environment variable
sqlplus / as sysdba

SQL>startup mount;
ORACLE instance started.
Total System Global Area 1068937216 bytes
Fixed Size 2166536 bytes
Variable Size 427819256 bytes
Database Buffers 624951296 bytes
Redo Buffers 14000128 bytes

it should became the mount stage then open the DB as follows SQL>alter database open;
Database altered.
Read more

Migrating From Oracle to PostgreSQL using ora2pg open source tools

-
In this blog we are going to talk about migrating from oracle to postgresql using ora2pg.
After installing ora2pg tool, we will see how to configure and to run it to migrate our data. We are using an oracle 12C database and a postgresql edb 9.6, The server is runing on OEL 7.2,The oracle database and the postgresql server are running on the same server.

we are going to talk about migrating from oracle to postgresql using ora2pg open source tool
before migrating you need to know little bit knowledge of functions,procedure,trigger and  Difference between oracle vs postgresql data types

1.Oracle Installation 12C
2.Oracle instalaltion 11gr2
3.postgresql installation 9.3
4.postgresql installation 10.3
-------------------------At Oracle---------------------------------------------------
PREREQUEST:
1.In a database all schema size:
set linesize 150 set pagesize 5000 col owner for a15 col segment_name for a30 col segment_type for a20 col TABLESPACE_NAME for a30 clear breaks clear computes compute sum of…
Read more