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PODB2 - handling columns defined as null
 

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    <p>Let's say you have three textboxes that you can use to search for data. Each textbox will correspond to a column on the DB2 table. The search string you enter will be inserted into the where clause. For example, you have First-Name, Last-Name, and Phone Number. If you don't enter data into a particular textbox, I default its value in the where clause to '_', the wildcard character to select everything. Also, lets say Phone Number is defined as NULL on the table.</p> <p>Cursor1 will be used if the user has entered a Phone number to search for. So the where clause will look something like this:</p> <p>Where FIRST_NAME like :firstname AND LAST_NAME like :lastname AND PHONE_NBR like :number</p> <p>This works when data is entered for phone number. But if a search is done for First Name only, the cursor returns partial or no results because the :number host variable will be populated with the "_' wildcard. PHONE_NBR like '_' will only return the rows that have a real value. If there is a null for PHONE_NBR on a row that matches the First Name you searched for, that row won't show up. So I created a second cursor.</p> <p>Cursor2 will be used if the user HAS NOT entered a Phone number to search for. The Where clause looks something like this.</p> <p>Where FIRST_NAME like :firstname AND LAST_NAME like :lastname AND (PHONE_NBR like :number OR PHONE_NBR IS NULL)</p> <p>So again, if a search was done for a first name only, and some values in PHONE_NBR have data, some are null, EVERYTHING that matches the first name that is searched for will show in the results - which is good. For the rows with values in PHONE_NBR, PHONE_NBR like '_' will get those. For the rows with null in PHONE_NBR, PHONE_NBR IS NULL will get those.</p> <p><em><strong>This is a minor yet necessary difference. Because of this minor difference, I would like to combine these two cursors into one. How can that be done to achieve the same results?</em></strong></p>
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    1. USWar Chester Shire Sauce
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    1. CONot sure what you're asking. The second cursor will include all rows that were in the first cursor plus any rows that contain NULLs for PHONE_NBR.
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      1. USIan Bjorhovde
 

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