How to speed up insertion performance in PostgreSQL

Disable any triggers on the table

Drop indexes before starting the import, re-create them afterwards. (It takes much less time to build an index in one pass than it does to add the same data to it progressively, and the resulting index is much more compact).

Change table to  UNLOGGED

table without indexes, then change it to logged and add the indexes.Unfortunately in PostgreSQL 9.4 there's no support for changing tables from

UNLOGGED

to logged. 9.5 adds

ALTER TABLE ... SET LOGGED

to permit you to do this.

Remove Foreign Key Constraints

If doing the import within a single transaction, it's safe to drop foreign key constraints, do the import, and re-create the constraints before committing. Do not do this if the import is split across multiple transactions as you might introduce invalid data.

If possible, use

COPY

instead of

INSERT

s

If you can't use

COPY

consider using multi-valued

INSERT

s if practical. Don't try to list too many values in a single

VALUES

though; those values have to fit in memory a couple of times over, so keep it to a few hundred per statement.

Batch your inserts into explicit transactions, doing hundreds of thousands or millions of inserts per transaction. There's no practical limit AFAIK, but batching will let you recover from an error by marking the start of each batch in your input data.

Increase maintenance_work_mem:This will help to speed up CREATE INDEX commands and ALTER TABLE ADD FOREIGN KEY commands. It won't do much for COPY itself, so this advice is only useful when you are using one or both of the above techniques.

Use

synchronous_commit=off

and a huge

commit_delay

to reduce fsync() costs. This won't help much if you've batched your work into big transactions, though.

INSERT

or

COPY

in parallel from several connections. How many depends on your hardware's disk subsystem; as a rule of thumb, you want one connection per physical hard drive if using direct attached storage.

Set a high

checkpoint_segments

value and enable

log_checkpoints

. Look at the PostgreSQL logs and make sure it's not complaining about checkpoints occurring too frequently.

If and only if you don't mind losing your entire PostgreSQL cluster (your database and any others on the same cluster) to catastrophic corruption if the system crashes during the import, you can stop Pg, set

fsync=off

, start Pg, do your import, then (vitally) stop Pg and set

fsync=on

again. See WAL configuration. Do not do this if there is already any data you care about in any database on your PostgreSQL install. If you set

fsync=off

you can also set

full_page_writes=off

; again, just remember to turn it back on after your import to prevent database corruption and data loss. See non-durable settings in the Pg manual.

Run ANALYZE Afterwards

参考：
http://stackoverflow.com/questions/12206600/how-to-speed-up-insertion-performance-in-postgresql https://www.postgresql.org/docs/9.4/static/populate.html