Very Slow Queries on MDB

Symptom:

Queries or Automation Actions that run on specific tables may take several seconds, minutes, or even seem to freeze ClayCentral for a few minutes when the database is MDB.

MDB performs badly when queries become too complex and there are many records and/or joins. For example:

• Queries on tables with 100,000s or 1,000,000s of records.
• Queries on tables with 10,000s of records and over 15 linked fields.
• Queries with multiple columns and filters from multiple tables, causing complex joins between numerous tables, some of them with 10,000s of records.
• Analysis queries with over 10 indicators and 10,000s of records.

Solutions:

Adding filters, adding indexes, removing query columns or indicators, and deleting unneeded linked fields usually helps. See also Increasing Digital-Clay Performance for tips that may help in specific scenarios.

If queries still run slow after the above tips, then the only solution is to move to SQL Server.