Count DataWindow expression function
Description
Calculates the total number of rows in the specified column.
Syntax
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1 |
<span>Count</span> ( <span>column</span> { FOR <span>range</span> { DISTINCT { <span>expres1</span> {, <span>expres2</span> {, ... } } } } } ) |
|
Argument |
Description |
|---|---|
|
column |
The column for which you want the number |
|
FOR range (optional) |
The data that will be included in the
For Crosstabs, specify CROSSTAB for range:
For Graph and OLE objects, specify one of the following:
|
|
DISTINCT (optional) |
Causes Count to consider |
|
expresn (optional) |
One or more expressions that you want |
Usage
If you specify range, Count determines
the number of rows in column in range. If
you specify DISTINCT, Count returns the number
of the distinct rows displayed in column, or
if you specify expresn, the number of rows
displayed 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:
-
For the Graph or OLE presentation
style, Rows is always All. -
For Graph controls, Rows can be All, Page, or Group.
-
For OLE controls, Rows can be All, Current Row,
Page, or Group. The available choices depend on the layer the control
occupies.
Null values in the column are ignored and are not included
in the count.
Not 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
This expression returns the number of rows in the
column named emp_id that are not null:
|
1 |
<span>Count</span>(emp_id) |
This expression returns the number of rows in the
column named emp_id of group 1 that are not null:
|
1 |
<span>Count</span>(emp_id for group 1) |
This expression returns the number of dept_ids
that are distinct:
|
1 |
<span>Count</span>(dept_id for all DISTINCT) |
This expression returns the number of regions with
distinct products:
|
1 |
<span>Count</span>(region_id for all DISTINCT Lower(product_id)) |
This expression returns the number of rows in column
3 on the page that are not null:
|
1 |
<span>Count</span>(#3 for page) |