Databases Reference
In-Depth Information
Tracing script
Another option that can be used to debug your scripts is the
Trace
statement. This
statement is called from the script and can be used to write all sorts of (debug)
information to the
Script Execution Progress
window.
For example, we can check if the amount of rows in the
Aircraft Types
changes
after we add the
left join
command to the data from the
Aircraft_Group.csv
ile
to it. This is done by putting the following code before and after the statement.
LET vNoOfRows = NoOfRows('Aircraft Types');
TRACE >>> Number of rows in Aircraft Types: $(vNoOfRows);
The first line of this script uses the
No Of Rows()
function to assign the value of the
number of rows in the
Aircraft Types
table to the
vNoOfRows
variable. The
second line uses the
TRACE
statement to write this value to the
Script Execution
Progress
window.
The result is shown in the following screenshot; we can see that there are
369
rows
before and after the
left join
statement, in the table.
Now that we have seen the various options for debugging our QlikView scripts, it is
time to think about how to keep things tidy and understandable.
