I am going to continue my series of very short articles or tidbits on Transaction SQL string functions. I will exploring the LOWER() function today.
The LOWER() function takes a source string as input and returns a output string with all alpha characters converted to lower case.
The following example converts the favorite movie title of mine to lower case.
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-- Make my string lower case select lower('WIZARD OF OZ') as str_phrase |
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output: str_phrase ------------ wizard of oz </span> |
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 lower('') as str_phrase -- Null returns Null select lower(NULL) as str_phrase |
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output: str_phrase ---------- str_phrase ---------- NULL |
Next time, I will be exploring the LTRIM() function.