I am going to continue my series of very short articles or tidbits on Transaction SQL string functions. I will exploring the UPPER() function today.
The UPPER() function takes a source string as input and returns a output string with all alpha characters converted to upper case.
The following example converts the favorite movie title of mine to upper case.
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-- Make my string upper case select upper('wizard of oz') as str_phrase |
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output: str_phrase ------------ WIZARD OF OZ |
One thing to always worry about when using TSQL functions is how will it react with empty strings or NULL values? Both empty strings and NULL values as input return themselves as output.
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-- Empty string returns empty string select upper('') as str_phrase -- Null returns Null select upper(NULL) as str_phrase |
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output: str_phrase ---------- str_phrase ---------- NULL |
This is the final string function to review in the SQL Server 2012 T-SQL language reference.
