SQLite3 Decimal

SQLite3 Decimal is an extension for SQLite3 implementing (exact) decimal arithmetic.

WARNING: this library is NOT ready for production. Use at your own risk!

There is no manual or official documentation yet. Please refer to the code documentation instead.

Quick Start

./configure
make
sqlite3 --cmd '.load ./libsqlite3decimal sqlite3_decimal_init'

Sample Session

sqlite> select decVersion();
Decimal v0.0.1 (decNumber 3.68)

sqlite> select decStr(decMul(decAdd('1.23', '45.0967', '-678.00000000000000001'), '-0.7891'));
498.453401030000000007891


sqlite> create table T(n blob); -- Decimals are stored as blobs
sqlite> insert into T values (dec('.843')), (dec('3427.19')), (dec('-28383.89'));
sqlite> select decStr(decMin(n)), decStr(decMax(n)), decStr(decSum(n)), decStr(decAvg(n)) from T;
-28383.89|3427.19|-24955.857|-8318.619

sqlite> select decStr(n) from T where n < dec(1);
0.843
-28383.89

sqlite> select decStr(decDiv(1,7));
0.142857142857142857142857142857142857143
sqlite> select * from decStatus; -- Was the result rounded?
Inexact result
Rounded result

sqlite> select * from decTraps; -- Which errors are trapped by default?
flag             
-----------------
Conversion syntax
Division by zero 
Division impossib
Division undefine
Out of memory    
Invalid context  
Invalid operation
Overflow         
Underflow        

sqlite> insert into decTraps values ('Inexact result');
sqlite> select decDiv(1,7);
Error: Inexact

sqlite> select dec('abc');
Error: Conversion syntax
sqlite> delete from decTraps where flag = 'Conversion syntax';
sqlite> select decStr(dec('abc'));
NaN               

sqlite> delete from decStatus; -- Clear the status flags

sqlite> select * from decContext;
prec        emax        emin        round        
----------  ----------  ----------  -------------
39          999999999   -999999999  ROUND_HALF_UP

sqlite> update decContext set prec = 6;
sqlite> select * from decContext;
prec        emax        emin        round        
----------  ----------  ----------  -------------
6           999999999   -999999999  ROUND_HALF_UP

sqlite> select decStr(dec('1.23456789'));
decStr(dec('1.23456789'))
-------------------------
1.23457