I am going to write a series of very short articles or tidbits on Transaction SQL (TSQL) functions. I will start exploring the string functions today in alphabetical order.
Before the invention of UNICODE, we were able to express only 128 different characters with 7 bit ASCII code.
Transaction SQL (TSQL) still supports the ASCII() function that takes a CHAR or VARCHAR datatype as input and returns a INT datatype as output.
The following example returns the ASCII code for a space which is a value of 32.
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-- A simple space declare @var_tmp char = ' '; -- Return ascii # select ascii(@var_tmp) as ascii_code; |
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output: ascii_code ----------- 32 |
One thing to always worry about when using TSQL functions is how will it react with a UNKNOWN or NULL value?
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-- A unknown value declare @var_tmp char = NULL; -- Return ascii # select ascii(@var_tmp) as ascii_code; |
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output: ascii_code ----------- NULL |
Next time, I will be exploring the CHAR() function.
