Anything you store in MongoDB’s GridFS is stored in 2 collections. For instance if your files are loaded in a GridFS bucket called ‘images’ you […]
Database, SQL, SQL Server
Parse delimited string into rows
Some time ago I had to build an integration app that would on occasion query from a SQL Server 2012 database and based on the […]
Database, Hacks, MongoDB, UNIX/Linux
Compile and install MongoDB on Raspberry PI
A 32 bit version of Raspbian is currently the most common OS that runs on a Raspberry PI. RPI 3 comes equipped with a 64 […]
Database, MongoDB
Join Array in MongoDB
Since version 3.2 you can use the $lookup to perform the equivalent of left outer joins in MongoDB. While you should try to design your […]
Database, MongoDB
When to use MongoDB $and Operator
On the surface, it seems like the $and operator is useless because it is implicitly applied when MongoDB processes each expression in the query. For […]
Database, MongoDB
MongoDB Aggregation to Custom Sort
While the MongoDB Aggregation Pipeline can be used to aggregate your data, it is definitely not limited to that and can be used to construct […]
Database, Java, MongoDB
MongoDB ClassCastException with new GridFS API
Starting with the MongoDB Java API 3.1 a new GridFS API has been added. It is available under the com.mongodb.client.gridfs package. If you are building […]
Database, MongoDB
Join Query in MongoDB
As a general rule, you should try to avoid joining as much as possible in MongoDB. While in traditional relational databases you try to avoid […]
Database, SQL, SQL Server
How to achieve the LIKE IN effect in SQL Server
SQL Server does not natively support a “LIKE IN” clause. For instance the following example is not valid: Luckily there is a way to achieve […]
SQL, SQL Server
Remove leading zeroes from varchar
The following example shows one way how you can remove leading zeroes from a varchar column in SQL Server: Returns: