Historical version. PostgreSQL 8.3 has reached end of support. See the current manual.
39.3. Data Values in PL/Tcl
The argument values supplied to a PL/Tcl function's code are simply the input arguments converted to text form (just as if they had been displayed by a SELECT statement). Conversely, the return command will accept any string that is acceptable input format for the function's declared return type. So, within the PL/Tcl function, all values are just text strings.
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