wengland@stephsf.UUCP (Bill England) (06/10/90)
In Ingres esql my query is returning a type money into a c type of double. How can I manipulate the money value?? ie add, sub, mul ?? How can I convert it into a float or truncate it into an integer? Code examples would be greatly appreciated. Thanks in advance! +-------- | Bill England | Stephen Software Systems, Inc., Tacoma Wa. | wengland@stephsf.com +1 206 564 2122 | * * H -> He +24Mev * * * ... Oooo, we're having so much fun making itty bitty suns * * *
jkrueger@dgis.dtic.dla.mil (Jon) (06/12/90)
wengland@stephsf.UUCP (Bill England) writes: > In Ingres esql my query is returning a type money into a c type of double. > How can I manipulate the money value?? ie add, sub, mul ?? > How can I convert it into a float or truncate it into an integer? > Code examples would be greatly appreciated. The following has been tested on Pyramid 98x under OSx 4.4 on both INGRES 5.0/05a (pyr.u42/04) and INGRES 6.1/01u (pyr.u42/04). This does not imply a commitment by Ingres, Pyramid, the Department of Defense, or J. R. "Bob" Dobbs. Simple single table database: +-----+ | emp | name salary +-----+----------+-------------+ | Huck | $10000.00| | Tom | $50000.00| | Sid | $5000.00| +------------------------+ ESQL/C code: #include <stdio.h> #define NOT_FOUND 100 exec sql include sqlca; main(argc,argv) int argc; char *argv[]; { exec sql connect testdb1; list_table(); exec sql disconnect; } list_table() { exec sql begin declare section; char emp_name[12]; double emp_sal; exec sql end declare section; exec sql declare csr cursor for select trim(name), salary from emp; exec sql open csr; if (sqlca.sqlcode < 0) ing_error("can not open cursor csr"); while (!sqlca.sqlcode) { exec sql fetch csr into :emp_name, :emp_sal; if (sqlca.sqlcode < 0) ing_error("can not fetch into cursor csr"); else if (sqlca.sqlcode != NOT_FOUND) list_row(emp_name, emp_sal); else break; } exec sql close csr; } list_row(name, sal) char *name; double sal; { float f_sal; int int_sal; char str_sal[20]; f_sal = sal; int_sal = sal; sprintf(str_sal, "%d", (int) sal); printf("emp: %s sal: %.2f = %.2f = %d = %d digits\n", name, sal, f_sal, int_sal, strlen(str_sal)); printf(" +1K: %.2f -1K: %.2f doubled: %.2f\n", sal + 1000.0, sal - 1000.0, sal * 2.0); } ing_error(string) char *string; { error(string); exec sql disconnect; exit(-3); } error(string) char string[]; { exec sql begin declare section; char errmsg[258]; char *err_stmt = string; exec sql end declare section; fprintf(stderr,"ERROR: %s\n", string); exec sql copy sqlerror into :errmsg WITH 256; fprintf(stderr, "Aborting with error:\n%s\n%s\n", err_stmt, errmsg); } The output from that code running on that database: emp: Huck sal: 10000.00 = 10000.00 = 10000 = 5 digits +1K: 11000.00 -1K: 9000.00 doubled: 20000.00 emp: Tom sal: 50000.00 = 50000.00 = 50000 = 5 digits +1K: 51000.00 -1K: 49000.00 doubled: 100000.00 emp: Sid sal: 5000.00 = 5000.00 = 5000 = 4 digits +1K: 6000.00 -1K: 4000.00 doubled: 10000.00 Warnings: Money is NOT the same as float; rather, database objects of type money are returned into C objects of type float. Floats underflow; money columns do not. Floats lose precision; money maintains fixed point precision. However, the limits of IEEE double precision floats are about those of the current INGRES money ADT. The range of the floats is much higher, however. It would be possible, for instance, to add up everyone's salary into a float which could then be too large to store into the database in a money column. This is a specific example of a more general problem of better query languages, programming languages, and interfaces between them. While we're waiting for them to arrive, be ye warned! Floats are subtle and quick to anger, and do not behave identically to money. They are the "least worst" choice for money in most currently available general purpose programming languages. -- Jon -- Jonathan Krueger jkrueger@dtic.dla.mil uunet!dgis!jkrueger Drop in next time you're in the tri-planet area!
chesky@portia.Stanford.EDU (Snehylata Gupta) (06/13/90)
In article <147@stephsf.UUCP> wengland@stephsf.UUCP (Bill England) writes: > > In Ingres esql my query is returning a type money into a c type of double. > How can I manipulate the money value?? ie add, sub, mul ?? > How can I convert it into a float or truncate it into an integer? > > Code examples would be greatly appreciated. > > > Thanks in advance! > > +-------- > | Bill England > | Stephen Software Systems, Inc., Tacoma Wa. The following will work The following will work float4_var = float4(money_var) or float8_var = float8(money_var) converts to float type variables to convert to integer the function names are int1, int2 and int4 which convert the datatype to the appropriate integer types. Sanjay using this account temporarily.