![]() onFooter is used when we want to display some information in the footer, such as a sales total or a legend for a line graph. Always writing the else clause is just good programming, since it documents what's actually happening and give you location in case you would to replace that implicit null with an explicit value. This event occurs after the processing of the grid lines, during the display of the HTML elements of the page footer. ![]() Yes, but you want to tell people that there is a default "ELSE NULL" implicit when it is left off. Sum(CASE WHEN > The ELSE argument is optional. Yet another usage would be good to share. Nice collection of scenarios and use of Case statements. I do always keep the original case as comment for readability :-) Try this on a table selecting a few miljon rows NULLIF and ISNULL are set based, and not RBAR ( row by agonizing row ) and by this a lot more performant. This calendar is a modal link from a grid based on the same table as the calendar/form. I click on a record in the calendar which brings up the form and change something and click save and the calendar is still there. MaritalStatusDesc = ISNULL(NULLIF(ISNULL(NULLIF(,'S'), 'Single'),), 'Married' ) I put that code in the onAfterUpdate event. MaritalStatusDesc = CASE WHEN = 'S' THEN 'Single' ELSE 'Married' END The CASE solution however is much more readable and thus easier to maintain. ![]() The second query is a little bit slower, but this might just be noise. Scan count 1, logical reads 26633, physical reads 0, read-ahead reads 0, lob logical reads 0, lob physical reads 0, lob read-ahead reads 0.ĬPU time = 719 ms, elapsed time = 8456 ms.ĬPU time = 1109 ms, elapsed time = 9230 ms.Īs you can see, logical reads are exactly the same. Example: After updating a record in the database, we want to store the update operation. The form will then execute the onValidate, onValidateSuccess and onBeforeUpdate events, and right after executing the SQL command to insert the database record, it will execute the onAfterUpdate event. The results (CASE is first, isnull(nullif()) second): This event occurs after clicking the forms Save button. The execution plans are almost exact the same, and both get 50% of the cost. Our documentation is updated continuously, according to the launch of new functionalities. I've blown up the Employee table to a little more than a million rows, so I could test performance between the two statements. A complete online documentation for all the features of the Scriptcase development environment. However, I've never understood the notion that CASE would be RBAR and thus inherently slow. ISNULL(NULLIF(ISNULL(NULLIF(CONVERT(VARCHAR(50),),'S'), 'Single'),), 'Married' ) Your expression currently doesn't work, because MaritalStatus is only one character long, so all other columns are converted to this data type, which leads to incorrect results (all results are M).
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