Max

Description

Gets the maximum value in the specified column.

Syntax

Max ( column { FOR range { DISTINCT { expres1 {, expres2 {, ... } } } } } )

Argument

Description

column

The column for which you want the maximum value. Column can be the column name or the column number preceded by a pound sign (#). Column can also be an expression that includes a reference to the column. The datatype of column must be numeric.

FOR range (optional)

The data that will be included when the maximum value is found. For most presentation styles, values for range are:

  • ALL – (Default) The maximum value of all rows in column.

  • GROUP n – The maximum value of rows in column in the specified group. Specify the keyword GROUP followed by the group number: for example, GROUP 1.

  • PAGE – The maximum value of the rows in column on a page.

For Crosstabs, specify CROSSTAB for range:

  • CROSSTAB – (Crosstabs only) The maximum value of all rows in column in the crosstab.

For Graph and OLE objects, specify one of the following:

  • GRAPH – (Graphs only) The maximum value in column in the range specified for the Rows option.

  • OBJECT – (OLE objects only) The maximum value in column in the range specified for the Rows option.

DISTINCT (optional)

Causes Max to consider only the distinct values in column when determining the largest value. For a value of column, the first row found with the value is used and other rows that have the same value are ignored.

expresn (optional)

One or more expressions that you want to evaluate to determine distinct rows. Expresn can be the name of a column, a function, or an expression.

Returns

The datatype of the column. Returns the maximum value in the rows of column. If you specify range, Max returns the maximum value in column in range.

Usage

If you specify range, Max determines the maximum value in column in range. If you specify DISTINCT, Max returns the maximum distinct value in column, or if you specify expresn, the maximum distinct value in column where the value of expresn is distinct.

For graphs and OLE objects, you do not select the range when you call the function. The range has already been determined by the Rows setting on the Data property page (the Range property), and the aggregation function uses that range. Settings for Rows include the following:

Null values are ignored and are not considered in determining the maximum.

NoteNot in validation rules or filter expressions You cannot use this or other aggregate functions in validation rules or filter expressions.

Using an aggregate function cancels the effect of setting Retrieve Rows As Needed in the painter. To do the aggregation, a DataWindow object always retrieves all rows.

Examples

Example 1

This expression returns the maximum of the values in the age column on the page:

Max(age for page)

Example 2

This expression returns the maximum of the values in column 3 on the page:

Max(#3 for page)

Example 3

This expression returns the maximum of the values in the column named age in group 1:

Max(age for group 1)

Example 4

Assuming a DataWindow object displays the order number, amount, and line items for each order, this computed field returns the maximum of the order amount for the distinct order numbers:

Max(order_amt for all DISTINCT order_nbr)

See also