When converting TDS-PACKED-DECIMAL data to character datatypes, you must adjust the length of the result variable.
Use this formula to set the unpacked length:
Result Length = (2 * Source Length) - 1.
When converting to character datatypes, automatic conversions may add a sign, a decimal point, and leading or trailing zeros. Allow one byte each for the sign and decimal point, and enough bytes to allow for the leading and trailing zeros.
When converting from packed decimal to character datatypes, Gateway-Library functions add zeros to the left of the decimal point for fractional values and to the right of the decimal point for integers. If no decimal point is present, one is added.
For all values, start with the defined length (precision).
Add 1 byte for the sign:
If the sign is positive, Open ServerConnect adds a blank.
If the sign is negative, Open ServerConnect adds a minus sign.
For integer values:
Add one byte for a decimal point
Add one byte for a trailing zero
For fractional values, (n < 1 and > -1, precision = scale):
Add one byte for a decimal point
Add one byte for a leading zero
For non-integer values greater than 1:
Add one byte for a decimal point
Table 2-10 lists decimal-to-character conversions.
Decimal value |
Precision |
Scale |
Calculation P+s+d+z = result length |
Character-type result |
Result length |
|---|---|---|---|---|---|
1 |
3 |
0 |
3+1+1+1 = 6 |
bbb1.0 |
6 |
123 |
3 |
0 |
3+1+1+1 = 6 |
b123.0 |
6 |
-123 |
3 |
0 |
3+1+1+1 = 6 |
-123.0 |
6 |
1.23 |
5 |
2 |
5+1+1+0 = 7 |
bbb1.23 |
7 |
.3 |
5 |
2 |
5+1+1+0 = 7 |
bbb0.30 |
7 |
-.2 |
5 |
2 |
5+1+1+0 = 7 |
bb0.20 |
7 |
123.45 |
5 |
2 |
5+1+1+0 = 7 |
b123.45 |
7 |
.123 |
3 |
3 |
3+1+1+1 = 6 |
ThinSpaceb0.123 |
6 |
-.123 |
3 |
3 |
3+1+1+1 = 6 |
ThinSpace-0.123 |
6 |
For packed decimal-to-character conversions, the low-order digits of the character string are truncated. If the actual result is greater than the length of the destination, the low-order bytes are truncated.
For character-to-packed decimal conversions, the character string is scanned from left to right to determine precision and scale. The resulting packed decimal value contains the highest order digits that fit in the length specified by the destination length.
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