Convert char for bit data to integer in DB2

Question

I'm writing a DB2 user-defined function for which I need an array of non-negative integers, which I represent as a varchar for bit data. I plan to use two bytes for each integer (giving me a maximum value of 2^16-1, which is acceptable).

I can convert an integer to a char for bit data by using the chr function, but how do I get it back to an integer?

Any additional advice on bit manipulation in DB2 procedures would be helpful as well, as I can't seem to find much documentation on it. I'm using v9.1 on Linux.

Answer 1

I'm not sure if CHR is actually what you want. According to the documentation, the CHR function:

Returns the character that has the ASCII code value specified by the argument. The argument can be either INTEGER or SMALLINT. The value of the argument should be between 0 and 255; otherwise, the return value is null.

The opposite of the CHR function is the ASCII function.

Full list of DB2 scalar procedures is here.

I'm not sure if writing a UDF in this way is the best for what you're trying to do. You may want to consider writing a stored procedure that's not in SQL. There's a list of supported languages, like Java, C, C++ etc.