APL2 is a great tool for manipulating lots of different kinds of files. You can easily move data between APL2 and files that many of your other tools use.
If you need the power of a relational database, APL2 makes it easy to access DB2 or SQL/DS, using Structured Query Language.
APL2 lets you issue SQL requests and explore your database interactively, without any precompilation or other special preparation steps. You can access remote databases using distributed database support from IBM.
Unlike ordinary query tools, you can do a lot more than just display data. When you use APL2 to issue a database query, the results are placed in an array. You can display the array or you can perform calculations with it using simple APL2 expressions. You can then update database tables using SQL.
When you issue a database request from APL2, it's processed asynchronously -- so you can continue your work in APL2 while the relational database is retrieving query results or updating tables.
If you want to make complex databases simple, you need APL2.