Sql updating table values

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If columns were specified in the FOR UPDATE clause of the SELECT statement used to generate the cursor, only those columns can be updated.If no columns were specified or the select statement did not include a FOR UPDATE clause, all columns may be updated.Vonki solution below works: UPDATE [Sales_Lead].[dbo].[Sales_Import] SET [Account Number] = Retrieve Account Number. As well as being standard SQL and thus more portable it also will raise an error in the event of there being multiple joined rows on the source side (and thus multiple possible different values to use in the update) rather than having the final result be undeterministic. Don't update a value with the same value, it generates extra logging and unnecessary overhead.

-- Indicate this by changing their job (JOB) to NULL and their pay -- (SALARY, BONUS, COMM) values to zero in the EMPLOYEE table.

Sebastian covers a technique for this in a recent blog post: sqlity.net/en/2867/update-from-select This will tend to work across almost all DBMS which means learn once, execute everywhere. Col2 AS _Col2 FROM T1 JOIN T2 ON T1= T2/*Where clause added to exclude rows that are the same in both tables Handles NULL values correctly*/ WHERE EXISTS(SELECT T1. I know this is old, but just wanted to say this one worked for me.

If that is more important to you than performance you might prefer this answer, especially if your update is a one off to correct some data. My server wont allow FROM to be used in an UPDATE statement. This may be a niche reason to perform an update (for example, mainly used in a procedure), or may be obvious to others, but it should also be stated that you can perform an update-select statement without using join (in case the tables you're updating between have no common field).

Because of this indeterminacy, referencing other tables only within sub-selects is safer, though often harder to read and slower than using a join. [1] Set the value of column C1 in table T to 1, only in those rows where the value of column C2 is "a".

I have a database with account numbers and card numbers.

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