This week I had to do something new in SQL.  I needed to take a list of multiple route records for each driver and append the routes into single string for that driver.  This is relatively simple in a Crystal report, but not so simple in a SQL Query.  After I realized how complex this would be in a normal SQL query I searched to see if there was a simpler way.  What I found was that several databases have a function specifically designed for this task.

In SQL Server and Postgre SQL it is called String_Agg().
In Oracle and DB2 it is called ListAgg().
In MySQL it is called Group_Concat().

Even though SQL is considered a “standard” language, some function names and syntax will vary from one database to another. That is why I created a “cheat sheet” a few years ago that lists the most common SQL functions (with their correct syntax) for the 8 SQL flavors I encounter the most:

• • • SQL Server
    • MySQL
    • Oracle
    • MS Access
    • Pervasive
    • Progress
    • PostgeSQL
    • DB2

Today I added these “aggregate” functions to the cheat sheet along with a few other updates.  The cheat sheet is now also available on the library page of my web site.