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## firstval

firstval — aggregate function to return the first value from a specified column.

## SYNOPSIS

`firstval (`expr`)`

## DESCRIPTION

This function returns the first value in the range of values returned by its query predicate.

Expression `expr` must contain the name of a column in a LiveView table. The returned first value is of the same type as the specified column.

If the query returns no rows, the aggregate returns `null` when group-by is not specified, and no rows when a group-by is specified.

## EXAMPLE

This example shows a simple use of the firstval() function.

1. In LiveView Desktop connected to a server running the Hello LiveView sample, select the ItemsSales table from the Tables pane of the LiveView Tables view.

2. In the Select field, enter:

       firstval(Item) as First

3. Make sure the Query field is empty.

4. Click Open Query.

The query results open in a grid view.

## SEE ALSO

This LiveView aggregate function is based on the firstval aggregate function in the StreamBase expression language.