Postgres query result returned as readable stream
Receive result rows from pg as a readable (object) stream.
$ npm install pg$ npm install pg-query-stream
$ npm install pg.js$ npm install pg-query-stream
var pg = require'pg'var QueryStream = require'pg-query-stream'var JSONStream = require'JSONStream'//pipe 1,000,000 rows to stdout without blowing up your memory usagepgconnectiferr throw err;var query = 'SELECT * FROM generate_series(0, $1) num' 1000000var stream = clientqueryquery//release the client when the stream is finishedstreamon'end' donestreampipeJSONStreamstringifypipeprocessstdout
The stream uses a cursor on the server so it efficiently keeps only a low number of rows in memory.
This is especially useful when doing ETL on a huge table. Using manual
offset queries to fake out async itteration through your data is cumbersom, and way way way slower than using a cursor.
I'm very open to contribution! Open a pull request with your code or idea and we'll talk about it. If it's not way insane we'll merge it in too: isn't open source awesome?
The MIT License (MIT)
Copyright (c) 2013 Brian M. Carlson
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