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PostgreSQL Interview Q & A For Experience -2

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1.how to set up pgbouncer connection pooling with postgres?
Postgreslq PgBouncer SetUp

2.what is ur backup startegy?
Daily taking basebaackup,if client request to taking particular objects means i will use pg_dump,pg_dumpall is used taking full cluser backup.

3.what is ur database size,and how long ur taking backup;
our environment db size is 500gb totally we have 60 db

4.why we use hot standby and slave?
  • Rplication provides a comprehensive set of services that create, maintain, manage, and monitor one or more slave(standby database) to enable production postgres server to survive disasters and data corruptions. 
  • Rplication maintains these slave databases as transactionally consistent copies of the production database.
5.if iam selecting select queriy in slaven,if it is wrok or not?
only hot and streaming replication standby only will be permit to use select query,
but warm standby will not be permit to use select query we cannot connect to the standby if warm standby

6.R u done any migration ? and which version r u using?
If you done migration means tell to "YES" and also you need to prepare migration steps
otherwise you can tell "NO" if you do not done.

7.application team want to which replication is best,what is ur suggestion?

Streaming replication is best BECAUSE
Warm Standby(8.3):
  • only records in a filled file are shipped, what's referred to as file-based log-shipping
  • warm standby was also configured for record-based shipping (which is complicated to setup).
  • We cannot connect to slave (stanby database)  

Streaming Replication:
  • XLOG records in partially-filled XLOG file are shipped too, implementing "record-based log-shipping" .
  • data loss smaller than warm standby becouse xlog records partially filled xlog file are shiped.
  • XLOG records shipped are replayed as soon as possible without waiting until XLOG file has been filled.
  • The standby periodically removes old XLOG files to prevent excessive disk usage.
  • we can connect and read records in standby.



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