# Check formulas

Whenever you change something in your TeamDesk database, it also updates all related places. Yet, updating the formula is not an easy task. Suppose you had the “ZipCode” text column and a formula doubling the column value. Then you changed the column type from text to numeric. Or you simply deleted the column. What result the formula should calculate now? Zero? Nonsense!

It's not possible to guess how the formula should be modified to produce still meaningful result. It's likely you, as a database administrator should decide if the formula is still relevant and how it should be modified. So far, when you are trying to delete a column, TeamDesk produces extensive usage report and leaves formula code intact, even if it would be invalid. Yet, if you do massive changes in your database, you may forget to patch all involved formulas. To fix them, use the Check formulas tool.

Setup > Database tab > Tools you can find Check Formulas tool listing all problematic formulas in your database.

Fig. ‘Check formula errors’

Also, if you have at least one formula validation error, the red banner is displayed on the setup overview pages.

Fig. ‘Formula Errors Banner’

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