column_ifexists()

Learn how to use the column_ifexists() function to return a reference to the column if it exists.

Displays the column, if the column exists. Otherwise, it returns the default column.

Syntax

column_ifexists(columnName,defaultValue)

Parameters

NameTypeRequiredDescription
columnNamestring✔️The name of the column to return.
defaultValuescalar✔️The default column to return if columnName doesn’t exist in the table. This value can be any scalar expression. For example, a reference to another column.

Returns

If columnName exists, then returns the column. Otherwise, it returns the defaultValue column.

Example

This example returns the default State column, because a column named Capital doesn’t exist in the StormEvents table.

StormEvents | project column_ifexists("Capital", State)

Output

This output shows the first 10 rows of the default State column.

State
ATLANTIC SOUTH
FLORIDA
FLORIDA
GEORGIA
MISSISSIPPI
MISSISSIPPI
MISSISSIPPI
MISSISSIPPI
AMERICAN SAMOA
KENTUCKY
…