Use a PostgreSQL result cursor from node with an easy to use API.
Sometimes you need to iterate through a table in chunks. It's extremely inefficient to use hand-crafted
OFFSET queries to do this.
PostgreSQL provides built-in functionality to fetch a "cursor" to your results and page through the cursor efficiently fetching chunks of the results with full MVCC compliance.
This actually ends up pairing very nicely with node's asyncness and handling a lot of data. PostgreSQL is rad.
var Cursor =var pg =pg;
Creates an instance of a query cursor. Pass this instance to node-postgres
rowCount rows from the cursor instance. The
If the cursor has read to the end of the result sets all subsequent calls to
cursor#read will return a 0 length array of rows. I'm open to other ways to signal the end of a cursor, but this has worked out well for me so far.
result is a special https://github.com/brianc/node-postgres/wiki/Query#result-object object that can be used to accumulate rows.
Closes the backend portal before itterating through the entire result set. Useful when you want to 'abort' out of a read early but continue to use the same client for other queries after the cursor is finished.
$ npm install pg-cursor
note: this depends on either
npm install pg or
The MIT License (MIT)
Copyright (c) 2013 Brian M. Carlson
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