SUM never gives an error. An integer result is returned for exact results
and a floating point result is returned for approximate results. Tickets #1664, #1669, and #1670. (CVS 3066) FossilOrigin-Name: 9e04f8fdf1ec0dc36effb55c05d075b3b4777fef
This commit is contained in:
drh
parent
cf85a51c2a
commit
29d7210819
26
manifest
26
manifest
@ -1,5 +1,5 @@
|
||||
C Deprecate\sthe\ssqlite3_aggregate_count()\sAPI.\s\sMake\ssure\sall\saggregate\scounters\nare\s64\sbits.\s\sRemove\sunused\sStdDev\sstructure\sfrom\sfunc.c.\s\sTicket\s#1669.\s(CVS\s3065)
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D 2006-02-09T18:35:30
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C SUM\snever\sgives\san\serror.\s\sAn\sinteger\sresult\sis\sreturned\sfor\sexact\sresults\nand\sa\sfloating\spoint\sresult\sis\sreturned\sfor\sapproximate\sresults.\nTickets\s#1664,\s#1669,\sand\s#1670.\s(CVS\s3066)
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D 2006-02-09T22:13:42
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F Makefile.in 5d8dff443383918b700e495de42ec65bc1c8865b
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||||
F Makefile.linux-gcc 74ba0eadf88748a9ce3fd03d2a3ede2e6715baec
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||||
F README 9c4e2d6706bdcc3efdd773ce752a8cdab4f90028
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||||
@ -43,7 +43,7 @@ F src/date.c cd2bd5d1ebc6fa12d6312f69789ae5b0a2766f2e
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||||
F src/delete.c 56ab34c3a384caa5d5ea06f5739944957e2e4213
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||||
F src/experimental.c 1b2d1a6cd62ecc39610e97670332ca073c50792b
|
||||
F src/expr.c 1149c3380bfce27703f5e9bec7dfb8e51baaf9d9
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||||
F src/func.c 49f49131afb37d1f808e9b84029da8644fc4faf7
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F src/func.c 93d004b453a5d9aa754e673eef75d3c9527e0f54
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||||
F src/hash.c 8747cf51d12de46512880dfcf1b68b4e24072863
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F src/hash.h 1b0c445e1c89ff2aaad9b4605ba61375af001e84
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||||
F src/insert.c 7e931b7f06afbcefcbbaab175c02eff8268db33f
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@ -69,7 +69,7 @@ F src/random.c d40f8d356cecbd351ccfab6eaedd7ec1b54f5261
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F src/select.c daee9b20702ba51cf3807fc1b130edd8846e3e48
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||||
F src/server.c 087b92a39d883e3fa113cae259d64e4c7438bc96
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||||
F src/shell.c 738f55ed75fb36731e764bfdb40756ac43b90b08
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||||
F src/sqlite.h.in 57d43548b59eed5116a322fc85bef4e3fc8a6bcc
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||||
F src/sqlite.h.in 89120d384e949be60f36af0e9e9f1b2684a30d35
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||||
F src/sqliteInt.h 0121298397ac14eb468ab1ba9d488ac7ed7d88a1
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F src/table.c 486dcfce532685b53b5a2b5da8bba0ded6fb2316
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F src/tclsqlite.c 7764ab34df617b3d3cfd5f0fdf3444ed219c11d6
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@ -81,7 +81,7 @@ F src/test5.c 7162f8526affb771c4ed256826eee7bb9eca265f
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F src/test6.c 60a02961ceb7b3edc25f5dc5c1ac2556622a76de
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||||
F src/test7.c d28d3e62f9594923648fc6a8fb030eba36564ba1
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F src/test_async.c 6776f5027ca6378c116ff5ccc2fe41b908e33772
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F src/test_md5.c e688969fc7db0acd9e4f4e0c33332e00228af60f
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F src/test_md5.c 6c42bc0a3c0b54be34623ff77a0eec32b2fa96e3
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||||
F src/test_server.c 087b92a39d883e3fa113cae259d64e4c7438bc96
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||||
F src/tokenize.c 9ae9a59238eb97fbc61baea280563b91100518fb
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F src/trigger.c 4d3644cbd16959b568c95ae73493402be8021b08
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@ -89,10 +89,10 @@ F src/update.c 14be4ba2f438919b4217085c02feff569e6cf1f2
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F src/utf.c 1199766bbb0157931a83aa6eede6b6381177be64
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||||
F src/util.c 405f46fef062b476826d2c171ec21def29563b75
|
||||
F src/vacuum.c 3865673cc66acd0717ecd517f6b8fdb2a5e7924b
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||||
F src/vdbe.c 29c68f39ce8cba44814b0e1f3d909ef961eb28a7
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F src/vdbe.c c92d7a4d3476136b8ab440f1e0547fab24112b34
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F src/vdbe.h 8729a4ee16ff9aeab2af9667df3cf300ff978e13
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F src/vdbeInt.h eb3f86ab08ef11635bc78eb88c3ff13f923c233b
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F src/vdbeapi.c ee8e889d8b4df30e38cdcda63f4e9e515b292633
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F src/vdbeapi.c 54dfd0975151c859ec5b125d225ad5b3cb586497
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F src/vdbeaux.c 9bf50cdb6a6c40b8c06ca9a8d87cf90120a16797
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F src/vdbefifo.c 9efb94c8c3f4c979ebd0028219483f88e57584f5
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F src/vdbemem.c 2034e93b32c14bda6e306bb54e3a8e930b963027
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@ -164,7 +164,7 @@ F test/enc3.test 890508efff6677345e93bf2a8adb0489b30df030
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F test/expr.test 4e65cade931e14a0194eee41e33707e7af5f397a
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F test/fkey1.test 153004438d51e6769fb1ce165f6313972d6263ce
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F test/format4.test 9f31d41d4f926cab97b2ebe6be00a6ab12dece87
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F test/func.test 458898c38bbb94e59ba4d96eff05731579acec33
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F test/func.test ba6159745ecb0b1c7cb4b082b34d5b2b09270eec
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F test/hook.test 7e7645fd9a033f79cce8fdff151e32715e7ec50a
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F test/in.test 40feeebc7e38576255051aad428322be1545e0f1
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F test/index.test c478459611ded74745fee57f99f424da8a5f5fbd
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@ -221,7 +221,7 @@ F test/rollback.test 673cd8c44c685ad54987fe7f0eeba84efa09685d
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F test/rowid.test 040a3bef06f970c45f5fcd14b2355f7f4d62f0cf
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F test/safety.test 4a06934e45d03b8b50ebcd8d174eb0367d2fd851
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F test/schema.test 8a2ae440fb15f5798a68059e8746402f3137be46
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F test/select1.test f4ab4b66e7089f0c64b6df954e75bafe05aabc0d
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F test/select1.test 9991b12eb68fa86e0faa29f26f51986d80ce0c42
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F test/select2.test f3c2678c3a9f3cf08ec4988a3845bda64be6d9e3
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F test/select3.test 8fece41cd8f2955131b3f973a7123bec60b6e65e
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F test/select4.test c239f516aa31f42f2ef7c6d7cd01105f08f934ca
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@ -329,7 +329,7 @@ F www/fullscanb.gif f7c94cb227f060511f8909e10f570157263e9a25
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F www/index-ex1-x-b.gif f9b1d85c3fa2435cf38b15970c7e3aa1edae23a3
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F www/index.tcl 9e31e3df4fe9385b24fb30086361c51a3ae486b5
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F www/indirect1b1.gif adfca361d2df59e34f9c5cac52a670c2bfc303a1
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F www/lang.tcl 3f7472e77a8257fb7c61a14e7607de3005b3fa2d
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F www/lang.tcl 8761d4ce0dfd029a638cfd4c54422dd852ec6606
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F www/lockingv3.tcl f59b19d6c8920a931f096699d6faaf61c05db55f
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F www/mingw.tcl d96b451568c5d28545fefe0c80bee3431c73f69c
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F www/nulls.tcl ec35193f92485b87b90a994a01d0171b58823fcf
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@ -351,7 +351,7 @@ F www/tclsqlite.tcl bb0d1357328a42b1993d78573e587c6dcbc964b9
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F www/vdbe.tcl 87a31ace769f20d3627a64fa1fade7fed47b90d0
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F www/version3.tcl a99cf5f6d8bd4d5537584a2b342f0fb9fa601d8b
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F www/whentouse.tcl 97e2b5cd296f7d8057e11f44427dea8a4c2db513
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P c72b946198128cbceb12dffbdf4706d9fda0fd72
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R be1e635cafb90b5983ca91c9370b824f
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P 44bd7ba432123ec77904b862d11521f4ab96d2cf
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R dfa46f13c8dc60b1e9e94224c227881b
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U drh
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Z d6f4b8669c07081bb92ea3ba047fbeee
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Z 3323dfe512cf86b69d178e38ebdbf07d
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@ -1 +1 @@
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44bd7ba432123ec77904b862d11521f4ab96d2cf
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9e04f8fdf1ec0dc36effb55c05d075b3b4777fef
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34
src/func.c
34
src/func.c
@ -16,7 +16,7 @@
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** sqliteRegisterBuildinFunctions() found at the bottom of the file.
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** All other code has file scope.
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**
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** $Id: func.c,v 1.120 2006/02/09 18:35:30 drh Exp $
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** $Id: func.c,v 1.121 2006/02/09 22:13:42 drh Exp $
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*/
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#include "sqliteInt.h"
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#include <ctype.h>
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@ -819,7 +819,7 @@ typedef struct SumCtx SumCtx;
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struct SumCtx {
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LONGDOUBLE_TYPE sum; /* Sum of terms */
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i64 cnt; /* Number of elements summed */
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u8 seenFloat; /* True if there has been any floating point value */
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u8 approx; /* True if sum is approximate */
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};
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/*
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@ -830,18 +830,33 @@ struct SumCtx {
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** 0.0 in that case. In addition, TOTAL always returns a float where
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** SUM might return an integer if it never encounters a floating point
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** value.
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**
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** I am told that SUM() should raise an exception if it encounters
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** a integer overflow. But after pondering this, I decided that
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** behavior leads to brittle programs. So instead, I have coded
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** SUM() to revert to using floating point if it encounters an
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** integer overflow. The answer may not be exact, but it will be
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** close. If the SUM() function returns an integer, the value is
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** exact. If SUM() returns a floating point value, it means the
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** value might be approximated.
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*/
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static void sumStep(sqlite3_context *context, int argc, sqlite3_value **argv){
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SumCtx *p;
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int type;
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assert( argc==1 );
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p = sqlite3_aggregate_context(context, sizeof(*p));
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type = sqlite3_value_type(argv[0]);
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type = sqlite3_value_numeric_type(argv[0]);
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if( p && type!=SQLITE_NULL ){
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p->sum += sqlite3_value_double(argv[0]);
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p->cnt++;
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if( type==SQLITE_FLOAT ){
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p->seenFloat = 1;
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if( type==SQLITE_INTEGER ){
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p->sum += sqlite3_value_int64(argv[0]);
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if( !p->approx ){
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i64 iVal;
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p->approx = p->sum!=(LONGDOUBLE_TYPE)(iVal = (i64)p->sum);
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}
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}else{
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p->sum += sqlite3_value_double(argv[0]);
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p->approx = 1;
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}
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}
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}
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@ -849,13 +864,10 @@ static void sumFinalize(sqlite3_context *context){
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SumCtx *p;
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p = sqlite3_aggregate_context(context, 0);
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if( p && p->cnt>0 ){
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i64 iVal = (i64)p->sum;
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if( p->seenFloat ){
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if( p->approx ){
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sqlite3_result_double(context, p->sum);
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}else if( p->sum==(LONGDOUBLE_TYPE)iVal ){
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sqlite3_result_int64(context, iVal);
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}else{
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sqlite3_result_error(context, "integer overflow", -1);
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sqlite3_result_int64(context, (i64)p->sum);
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}
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}
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}
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@ -12,7 +12,7 @@
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** This header file defines the interface that the SQLite library
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** presents to client programs.
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**
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** @(#) $Id: sqlite.h.in,v 1.159 2006/02/09 18:35:30 drh Exp $
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** @(#) $Id: sqlite.h.in,v 1.160 2006/02/09 22:13:42 drh Exp $
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*/
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#ifndef _SQLITE3_H_
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#define _SQLITE3_H_
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@ -898,6 +898,7 @@ sqlite_int64 sqlite3_column_int64(sqlite3_stmt*, int iCol);
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const unsigned char *sqlite3_column_text(sqlite3_stmt*, int iCol);
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const void *sqlite3_column_text16(sqlite3_stmt*, int iCol);
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int sqlite3_column_type(sqlite3_stmt*, int iCol);
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int sqlite3_column_numeric_type(sqlite3_stmt*, int iCol);
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/*
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** The sqlite3_finalize() function is called to delete a compiled
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@ -1005,6 +1006,7 @@ const void *sqlite3_value_text16(sqlite3_value*);
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const void *sqlite3_value_text16le(sqlite3_value*);
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const void *sqlite3_value_text16be(sqlite3_value*);
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int sqlite3_value_type(sqlite3_value*);
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int sqlite3_value_numeric_type(sqlite3_value*);
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/*
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** Aggregate functions use the following routine to allocate
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@ -353,9 +353,6 @@ int Md5_Init(Tcl_Interp *interp){
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return TCL_OK;
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}
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/*
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**
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/*
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** During testing, the special md5sum() aggregate function is available.
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** inside SQLite. The following routines implement that function.
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64
src/vdbe.c
64
src/vdbe.c
@ -43,7 +43,7 @@
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** in this file for details. If in doubt, do not deviate from existing
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** commenting and indentation practices when changing or adding code.
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**
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** $Id: vdbe.c,v 1.541 2006/01/31 19:31:44 drh Exp $
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** $Id: vdbe.c,v 1.542 2006/02/09 22:13:42 drh Exp $
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*/
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#include "sqliteInt.h"
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#include "os.h"
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@ -189,6 +189,31 @@ static Cursor *allocateCursor(Vdbe *p, int iCur, int iDb){
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return pCx;
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}
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/*
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** Try to convert a value into a numeric representation if we can
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** do so without loss of information. In other words, if the string
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** looks like a number, convert it into a number. If it does not
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** look like a number, leave it alone.
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*/
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static void applyNumericAffinity(Mem *pRec){
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if( (pRec->flags & (MEM_Real|MEM_Int))==0 ){
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int realnum;
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sqlite3VdbeMemNulTerminate(pRec);
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if( (pRec->flags&MEM_Str)
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&& sqlite3IsNumber(pRec->z, &realnum, pRec->enc) ){
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i64 value;
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sqlite3VdbeChangeEncoding(pRec, SQLITE_UTF8);
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if( !realnum && sqlite3atoi64(pRec->z, &value) ){
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sqlite3VdbeMemRelease(pRec);
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pRec->i = value;
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pRec->flags = MEM_Int;
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}else{
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sqlite3VdbeMemRealify(pRec);
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}
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}
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}
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}
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/*
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** Processing is determine by the affinity parameter:
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**
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@ -220,31 +245,28 @@ static void applyAffinity(Mem *pRec, char affinity, u8 enc){
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}else if( affinity!=SQLITE_AFF_NONE ){
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assert( affinity==SQLITE_AFF_INTEGER || affinity==SQLITE_AFF_REAL
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|| affinity==SQLITE_AFF_NUMERIC );
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if( 0==(pRec->flags&(MEM_Real|MEM_Int)) ){
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/* pRec does not have a valid integer or real representation.
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** Attempt a conversion if pRec has a string representation and
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** it looks like a number.
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*/
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int realnum;
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sqlite3VdbeMemNulTerminate(pRec);
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if( (pRec->flags&MEM_Str)
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&& sqlite3IsNumber(pRec->z, &realnum, pRec->enc) ){
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i64 value;
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sqlite3VdbeChangeEncoding(pRec, SQLITE_UTF8);
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if( !realnum && sqlite3atoi64(pRec->z, &value) ){
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sqlite3VdbeMemRelease(pRec);
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pRec->i = value;
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pRec->flags = MEM_Int;
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}else{
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sqlite3VdbeMemNumerify(pRec);
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}
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}
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}else if( pRec->flags & MEM_Real ){
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applyNumericAffinity(pRec);
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if( pRec->flags & MEM_Real ){
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sqlite3VdbeIntegerAffinity(pRec);
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}
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}
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}
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/*
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** Try to convert the type of a function argument or a result column
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** into a numeric representation. Use either INTEGER or REAL whichever
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** is appropriate. But only do the conversion if it is possible without
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** loss of information and return the revised type of the argument.
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**
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** This is an EXPERIMENTAL api and is subject to change or removal.
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*/
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int sqlite3_value_numeric_type(sqlite3_value *pVal){
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Mem *pMem = (Mem*)pVal;
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applyNumericAffinity(pMem);
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storeTypeInfo(pMem, 0);
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return pMem->type;
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}
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/*
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** Exported version of applyAffinity(). This one works on sqlite3_value*,
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** not the internal Mem* type.
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@ -74,6 +74,7 @@ const void *sqlite3_value_text16le(sqlite3_value *pVal){
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int sqlite3_value_type(sqlite3_value* pVal){
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return pVal->type;
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}
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/* sqlite3_value_numeric_type() defined in vdbe.c */
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/**************************** sqlite3_result_ *******************************
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** The following routines are used by user-defined functions to specify
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@ -469,6 +470,13 @@ int sqlite3_column_type(sqlite3_stmt *pStmt, int i){
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return sqlite3_value_type( columnMem(pStmt,i) );
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}
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/* The following function is experimental and subject to change or
|
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** removal */
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/*int sqlite3_column_numeric_type(sqlite3_stmt *pStmt, int i){
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** return sqlite3_value_numeric_type( columnMem(pStmt,i) );
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**}
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*/
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/*
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** Convert the N-th element of pStmt->pColName[] into a string using
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** xFunc() then return that string. If N is out of range, return 0.
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@ -11,7 +11,7 @@
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# This file implements regression tests for SQLite library. The
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# focus of this file is testing built-in functions.
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#
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# $Id: func.test,v 1.46 2006/02/09 17:47:42 drh Exp $
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# $Id: func.test,v 1.47 2006/02/09 22:13:42 drh Exp $
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|
||||
set testdir [file dirname $argv0]
|
||||
source $testdir/tester.tcl
|
||||
@ -551,7 +551,9 @@ do_test func-18.10 {
|
||||
}
|
||||
} 0
|
||||
|
||||
# Ticket #1669: If an integer SUM overflows, throw an error, thus
|
||||
# Ticket #1669, #1670: I am told that if an integer overflow occurs
|
||||
# during a sum that the result should be an error. This strikes me
|
||||
# as being brittle. So I'm not doing it that way.
|
||||
# making the SQL-standard version SUM() even more useless than it
|
||||
# was before.
|
||||
#
|
||||
@ -563,11 +565,11 @@ do_test func-18.11 {
|
||||
}
|
||||
} integer
|
||||
do_test func-18.12 {
|
||||
catchsql {
|
||||
execsql {
|
||||
INSERT INTO t6 VALUES(1<<62);
|
||||
SELECT sum(x) - ((1<<62)*2.0+1) from t6;
|
||||
}
|
||||
} {1 {integer overflow}}
|
||||
} {0.0}
|
||||
do_test func-18.13 {
|
||||
execsql {
|
||||
SELECT total(x) - ((1<<62)*2.0+1) FROM t6
|
||||
|
||||
@ -11,7 +11,7 @@
|
||||
# This file implements regression tests for SQLite library. The
|
||||
# focus of this file is testing the SELECT statement.
|
||||
#
|
||||
# $Id: select1.test,v 1.47 2006/01/14 08:02:28 danielk1977 Exp $
|
||||
# $Id: select1.test,v 1.48 2006/02/09 22:13:42 drh Exp $
|
||||
|
||||
set testdir [file dirname $argv0]
|
||||
source $testdir/tester.tcl
|
||||
@ -211,7 +211,7 @@ do_test select1-2.17 {
|
||||
} {0 45}
|
||||
do_test select1-2.17.1 {
|
||||
execsql {SELECT sum(a) FROM t3}
|
||||
} {44}
|
||||
} {44.0}
|
||||
do_test select1-2.18 {
|
||||
set v [catch {execsql {SELECT XYZZY(f1) FROM test1}} msg]
|
||||
lappend v $msg
|
||||
@ -828,4 +828,3 @@ ifcapable subquery {
|
||||
}
|
||||
|
||||
finish_test
|
||||
|
||||
|
||||
33
www/lang.tcl
33
www/lang.tcl
@ -1,7 +1,7 @@
|
||||
#
|
||||
# Run this Tcl script to generate the lang-*.html files.
|
||||
#
|
||||
set rcsid {$Id: lang.tcl,v 1.107 2006/01/30 23:04:52 drh Exp $}
|
||||
set rcsid {$Id: lang.tcl,v 1.108 2006/02/09 22:13:42 drh Exp $}
|
||||
source common.tcl
|
||||
|
||||
if {[llength $argv]>0} {
|
||||
@ -1366,7 +1366,10 @@ values in column X.
|
||||
<tr>
|
||||
<td valign="top" align="right" width=120>avg(<i>X</i>)</td>
|
||||
<td valign="top">Return the average value of all non-NULL <i>X</i> within a
|
||||
group. Non-numeric values are interpreted as 0.</td>
|
||||
group. String and BLOB values that do not look like numbers are
|
||||
interpreted as 0.
|
||||
The result of avg() is always a floating point value even if all
|
||||
inputs are integers. </p></td>
|
||||
</tr>
|
||||
|
||||
<tr>
|
||||
@ -1391,15 +1394,23 @@ if all values in the group are NULL.</td>
|
||||
|
||||
<tr>
|
||||
<td valign="top" align="right">sum(<i>X</i>)<br>total(<i>X</i>)</td>
|
||||
<td valign="top">Return the numeric sum of all numeric values in the group.
|
||||
If there are no input rows or all values are NULL, then sum() returns
|
||||
NULL but total() returns zero.
|
||||
NULL is not a helpful result in that case (the correct answer should be
|
||||
zero) but the SQL standard requires that behavior from sum() and that is how
|
||||
most other SQL database engines implement sum() so SQLite does it that way
|
||||
in order to be compatible. The non-standard total() function is provided
|
||||
as a convenient way
|
||||
to work around this design problem in the SQL language.</td>
|
||||
<td valign="top">Return the numeric sum of all non-NULL values in the group.
|
||||
If there are no non-NULL input rows then sum() returns
|
||||
NULL but total() returns 0.0.
|
||||
NULL is not normally a helpful result for the sum of no rows
|
||||
but the SQL standard requires it and most other
|
||||
SQL database engines implement sum() that way so SQLite does it in the
|
||||
same way in order to be compatible. The non-standard total() function
|
||||
is provided as a convenient way to work around this design problem
|
||||
in the SQL language.</p>
|
||||
|
||||
<p>The result of total() is always a floating point value.
|
||||
The result of sum() is an integer value if all non-NULL inputs are integers
|
||||
and the sum is exact. If any input to sum() is neither an integer or
|
||||
a NULL or if the
|
||||
an integer overflow occurs at any point during the computation,
|
||||
then sum() returns a floating point value
|
||||
which might be an approximation to the true sum.</td>
|
||||
</tr>
|
||||
</table>
|
||||
}
|
||||
|
||||
Loading…
Reference in New Issue
Block a user