tlperkins / sqldown

sqlite3 backend for levelup

SQLdown

A levelup backend with knex (sqlite3, postgres, and mysql tested and websql possible).

npm install --save sqldown

Also it doens't come with any of the database backends so you need to install those yourself, one of

npm install --save sqlite3
npm install --save pg pg-query-stream
npm install --save mysql

In node locations should be connection strings (e.g. postgres://username:password@localhost/database), if it doesn't start with a 'dbType://' it is assumed to be the path for a local sqlite3 database. Table defaults to sqldown but can be overridden either by passing an table option or setting a query param (pg://localhost/database?table=tablename).

In the browser location will always be the table name.

Test setup and much else taken from level-js.

Setup

To get around the fact that postgres does not feature upserts instead of a simple table with 2 columns, key and value with key being the primary and unique key, instead we have a more complex setup with 3 columns id, key and value with id being an autoincremented integer. When we do gets we query for the value with the given key which has the highest id.

This could lead to much excess data if you were to update the same key a bunch so it's set to periodically (by default every 25 puts) clean up any entrys that arn't the max id for a given key.

Databases that support indexes on arbitrarily long fields have both the key and value fiels indexed. Or in other words MySql is slow because it dosn't support us indexing the important fields.