The Magic of SQL: Column Update Mystery

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You use the update statement in SQL to modify existing values in a row. Normally you have to assign values to each column explicitly. In this video Chris updates the value in one column and also changes the value in another column - without any triggers in sight!

Watch the video to see how it's done!

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The Magic of SQL with Chris Saxon

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Very fun learning, looking forward for more SQL magic

horiaberca
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Can the definition of virtual column be changed after data is entered into the column?

rajarajeshwaripremkumar
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If I have 10000+ rows, is there any effect on performance of select query??

Saurabhnaik
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Wouldn't it be better to just teach people why values that are not dependent on the primary key should not be in the table? Rather than adding a calculated virtual column?

michaelb