Add experimental date and time functions based on julian day number. (CVS 1069)

FossilOrigin-Name: a6197e2075fdf9db862484255ac16b2855bbef0a
This commit is contained in:
drh 2003-08-09 21:32:28 +00:00
parent 37ed48ed2f
commit 771d8c3bae
6 changed files with 349 additions and 12 deletions

View File

@ -1,5 +1,5 @@
C Provide\sa\smore\sinformative\serror\smessage\swhen\sa\suniqueness\sconstraint\nfails.\s\sTicket\s#419.\s(CVS\s1068)
D 2003-08-05T13:13:38
C Add\sexperimental\sdate\sand\stime\sfunctions\sbased\son\sjulian\sday\snumber.\s(CVS\s1069)
D 2003-08-09T21:32:28
F Makefile.in 9ad23ed4ca97f9670c4496432e3fbd4b3760ebde
F Makefile.linux-gcc b86a99c493a5bfb402d1d9178dcdc4bd4b32f906
F README f1de682fbbd94899d50aca13d387d1b3fd3be2dd
@ -29,14 +29,14 @@ F src/copy.c 9e47975ea96751c658bcf1a0c4f0bb7c6ee61e73
F src/delete.c 0f81e6799c089487615d38e042a2de4d2d6192bc
F src/encode.c 25ea901a9cefb3d93774afa4a06b57cb58acf544
F src/expr.c 03c321ac66c1e998c2e0faf22184b5a808b559ca
F src/func.c 6b23578d48a8be98a664db145a635c2fa9ddb57b
F src/func.c 67b66803d8a8b33dfea64ef54835d8b1d43c9f20
F src/hash.c 058f077c1f36f266581aa16f907a3903abf64aa3
F src/hash.h cd0433998bc1a3759d244e1637fe5a3c13b53bf8
F src/insert.c dc200ae04a36bd36e575272a069e20c528b7fbdf
F src/main.c 2500392bad5629b6d70b06ac5a076958acb49b92
F src/md5.c fe4f9c9c6f71dfc26af8da63e4d04489b1430565
F src/os.c b0ae51da6e2ec7dd9f48f92ac88985d5fde8c1d5
F src/os.h 8aed1c928449433acf19d30f76bc86d549041167
F src/os.c acb42a6524adb04cf4b98dd130f1f64657180bba
F src/os.h 4c51809f56daf21efbe26fc932998e865a5bc211
F src/pager.c a4fd3a61d63879365f775875edfffaa8c6f3d7f8
F src/pager.h 5da62c83443f26b1792cfd72c96c422f91aadd31
F src/parse.y 16aed0e3ed05445fa7f6a4209cc054208c7083c0
@ -47,7 +47,7 @@ F src/select.c 2fa83d6c972d3e3f379faee32e3621411490dedb
F src/shell.c c2ba26c850874964f5ec1ebf6c43406f28e44c4a
F src/shell.tcl 27ecbd63dd88396ad16d81ab44f73e6c0ea9d20e
F src/sqlite.h.in dafa83571810b6932f089b589c783355ef7a54b5
F src/sqliteInt.h a57cafea9ef34e73e4504ada4bc70417def67f1e
F src/sqliteInt.h cdcfdb5dca98359e443e23384b822a53ebd610ac
F src/table.c 4301926464d88d2c2c7cd21c3360aa75bf068b95
F src/tclsqlite.c d6860dcd56348b9521726280b72c412d2a33ae97
F src/test1.c b12b585bfb4763df3262975ed8d3f4f274b5eaed
@ -168,7 +168,7 @@ F www/speed.tcl 2f6b1155b99d39adb185f900456d1d592c4832b3
F www/sqlite.tcl 3c83b08cf9f18aa2d69453ff441a36c40e431604
F www/tclsqlite.tcl 1db15abeb446aad0caf0b95b8b9579720e4ea331
F www/vdbe.tcl 9b9095d4495f37697fd1935d10e14c6015e80aa1
P da6273255471673841fdcadc688aeac80722e130
R 1c0d64f5eac1f91d3d759569b9f6d88e
P 086aa1c9922b7bf399b3ee8b73ba7353d126b119
R b633d80bd522667187e3193065550fbf
U drh
Z cf08853c7690373b766f29a37d61c34c
Z 4776791846cfff06b30527d77321657f

View File

@ -1 +1 @@
086aa1c9922b7bf399b3ee8b73ba7353d126b119
a6197e2075fdf9db862484255ac16b2855bbef0a

View File

@ -16,13 +16,14 @@
** sqliteRegisterBuildinFunctions() found at the bottom of the file.
** All other code has file scope.
**
** $Id: func.c,v 1.26 2003/06/28 16:20:23 drh Exp $
** $Id: func.c,v 1.27 2003/08/09 21:32:28 drh Exp $
*/
#include <ctype.h>
#include <math.h>
#include <stdlib.h>
#include <assert.h>
#include "sqliteInt.h"
#include "os.h"
/*
** Implementation of the non-aggregate min() and max() functions
@ -497,6 +498,312 @@ static void minMaxFinalize(sqlite_func *context){
}
}
/****************************************************************************
** Time and date functions.
**
** SQLite processes all times and dates as Julian Day numbers. The
** dates and times are stored as the number of days since noon
** in Greenwich on January 01, 4713 B.C. (a.k.a -4713-01-01 12:00:00)
** This implement requires years to be expressed as a 4-digit number
** which means that only dates between 0000-01-01 and 9999-12-31 can
** be represented, even though julian day numbers allow a much wider
** range of dates.
**
** The Gregorian calendar system is used for all dates and times,
** even those that predate the Gregorian calendar. Historians often
** use the Julian calendar for dates prior to 1582-10-15 and for some
** dates afterwards, depending on locale. Beware of this difference.
**
** The conversion algorithms are implemented based on descriptions
** in the following text:
**
** Jean Meeus
** Astronomical Algorithms, 2nd Edition, 1998
** ISBM 0-943396-61-1
** Willmann-Bell, Inc
** Richmond, Virginia (USA)
*/
#ifndef SQLITE_OMIT_DATETIME_FUNCS
/*
** Convert N digits from zDate into an integer. Return
** -1 if zDate does not begin with N digits.
*/
static int getDigits(const char *zDate, int N){
int val = 0;
while( N-- ){
if( !isdigit(*zDate) ) return -1;
val = val*10 + *zDate - '0';
zDate++;
}
return val;
}
/*
** Parse dates of the form HH:MM:SS or HH:MM. Store the
** result (in days) in *prJD.
**
** Return 1 if there is a parsing error and 0 on success.
*/
static int parseHhMmSs(const char *zDate, double *prJD){
int h, m, s;
h = getDigits(zDate, 2);
if( h<0 || zDate[2]!=':' ) return 1;
zDate += 3;
m = getDigits(zDate, 2);
if( m<0 || m>59 ) return 1;
zDate += 2;
if( *zDate==':' ){
s = getDigits(&zDate[1], 2);
if( s<0 || s>59 ) return 1;
zDate += 3;
}else{
s = 0;
}
while( isspace(*zDate) ){ zDate++; }
*prJD = (h*3600.0 + m*60.0 + s)/86400.0;
return 0;
}
/*
** Parse dates of the form
**
** YYYY-MM-DD HH:MM:SS
** YYYY-MM-DD HH:MM
** YYYY-MM-DD
**
** Write the result as a julian day number in *prJD. Return 0
** on success and 1 if the input string is not a well-formed
** date.
*/
static int parseYyyyMmDd(const char *zDate, double *prJD){
int Y, M, D;
double rTime;
int A, B, X1, X2;
Y = getDigits(zDate, 4);
if( Y<0 || zDate[4]!='-' ) return 1;
zDate += 5;
M = getDigits(zDate, 2);
if( M<=0 || M>12 || zDate[2]!='-' ) return 1;
zDate += 3;
D = getDigits(zDate, 2);
if( D<=0 || D>31 ) return 1;
zDate += 2;
while( isspace(*zDate) ){ zDate++; }
if( isdigit(*zDate) ){
if( parseHhMmSs(zDate, &rTime) ) return 1;
}else if( *zDate==0 ){
rTime = 0.0;
}else{
return 1;
}
/* The year, month, and day are now stored in Y, M, and D. Convert
** these into the Julian Day number. See Meeus page 61.
*/
if( M<=2 ){
Y--;
M += 12;
}
A = Y/100;
B = 2 - A + (A/4);
X1 = 365.25*(Y+4716);
X2 = 30.6001*(M+1);
*prJD = X1 + X2 + D + B - 1524.5 + rTime;
return 0;
}
/*
** Attempt to parse the given string into a Julian Day Number. Return
** the number of errors.
**
** The following are acceptable forms for the input string:
**
** YYYY-MM-DD
** YYYY-MM-DD HH:MM
** YYYY-MM-DD HH:MM:SS
** HH:MM
** HH:MM:SS
** DDDD.DD
** now
*/
static int parseDateOrTime(const char *zDate, double *prJD){
int i;
for(i=0; isdigit(zDate[i]); i++){}
if( i==4 && zDate[i]=='-' ){
return parseYyyyMmDd(zDate, prJD);
}else if( i==2 && zDate[i]==':' ){
return parseHhMmSs(zDate, prJD);
}else if( i==0 && sqliteStrICmp(zDate,"now")==0 ){
return sqliteOsCurrentTime(prJD);
}else if( sqliteIsNumber(zDate) ){
*prJD = atof(zDate);
return 0;
}
return 1;
}
/*
** Break up a julian day number into year, month, day, and seconds.
** This function assume the Gregorian calendar - even for dates prior
** to the invention of the Gregorian calendar in 1582.
**
** See Meeus page 63.
*/
static void decomposeDate(double JD, int *pY, int *pM, int *pD, int *pS){
int Z, A, B, C, D, E, X1;
Z = JD + 0.5;
A = (Z - 1867216.25)/36524.25;
A = Z + 1 + A - (A/4);
B = A + 1524;
C = (B - 122.1)/365.25;
D = 365.25*C;
E = (B-D)/30.6001;
X1 = 30.6001*E;
*pD = B - D - X1;
*pM = E<14 ? E-1 : E-13;
*pY = *pD>2 ? C - 4716 : C - 4715;
*pS = (JD + 0.5 - Z)*86400.0;
}
/*
** Check to see that all arguments are valid date strings. If any is
** not a valid date string, return 0. If all are valid, return 1.
** Write into *prJD the sum of the julian day numbers for all date
** strings.
*/
static int isDate(
sqlite_func *context,
int argc,
const char **argv,
double *prJD
){
double r;
int i;
*prJD = 0.0;
for(i=0; i<argc; i++){
if( argv[i]==0 ) return 0;
if( parseDateOrTime(argv[i], &r) ) return 0;
*prJD += r;
}
return 1;
}
/*
** The following routines implement the various date and time functions
** of SQLite.
*/
static void juliandayFunc(sqlite_func *context, int argc, const char **argv){
double JD;
if( isDate(context, argc, argv, &JD) ){
sqlite_set_result_double(context, JD);
}
}
static void timestampFunc(sqlite_func *context, int argc, const char **argv){
double JD;
if( isDate(context, argc, argv, &JD) ){
int Y, M, D, h, m, s;
char zBuf[100];
decomposeDate(JD, &Y, &M, &D, &s);
h = s/3600;
s -= h*3600;
m = s/60;
s -= m*60;
sprintf(zBuf, "%04d-%02d-%02d %02d:%02d:%02d", Y, M, D, h, m, s);
sqlite_set_result_string(context, zBuf, -1);
}
}
static void timeFunc(sqlite_func *context, int argc, const char **argv){
double JD;
if( isDate(context, argc, argv, &JD) ){
int Y, M, D, h, m, s;
char zBuf[100];
decomposeDate(JD, &Y, &M, &D, &s);
h = s/3600;
s -= h*3600;
m = s/60;
s -= m*60;
sprintf(zBuf, "%02d:%02d:%02d", h, m, s);
sqlite_set_result_string(context, zBuf, -1);
}
}
static void dateFunc(sqlite_func *context, int argc, const char **argv){
double JD;
if( isDate(context, argc, argv, &JD) ){
int Y, M, D, s;
char zBuf[100];
decomposeDate(JD, &Y, &M, &D, &s);
sprintf(zBuf, "%04d-%02d-%02d", Y, M, D);
sqlite_set_result_string(context, zBuf, -1);
}
}
static void yearFunc(sqlite_func *context, int argc, const char **argv){
double JD;
if( isDate(context, argc, argv, &JD) ){
int Y, M, D, s;
decomposeDate(JD, &Y, &M, &D, &s);
sqlite_set_result_int(context, Y);
}
}
static void monthFunc(sqlite_func *context, int argc, const char **argv){
double JD;
if( isDate(context, argc, argv, &JD) ){
int Y, M, D, s;
decomposeDate(JD, &Y, &M, &D, &s);
sqlite_set_result_int(context, M);
}
}
static void dayofweekFunc(sqlite_func *context, int argc, const char **argv){
double JD;
if( isDate(context, argc, argv, &JD) ){
int Z = JD + 1.5;
sqlite_set_result_int(context, Z % 7);
}
}
static void dayofmonthFunc(sqlite_func *context, int argc, const char **argv){
double JD;
if( isDate(context, argc, argv, &JD) ){
int Y, M, D, s;
decomposeDate(JD, &Y, &M, &D, &s);
sqlite_set_result_int(context, D);
}
}
static void secondFunc(sqlite_func *context, int argc, const char **argv){
double JD;
if( isDate(context, argc, argv, &JD) ){
int Y, M, D, h, m, s;
decomposeDate(JD, &Y, &M, &D, &s);
h = s/3600;
s -= h*3600;
m = s/60;
s -= m*60;
sqlite_set_result_int(context, s);
}
}
static void minuteFunc(sqlite_func *context, int argc, const char **argv){
double JD;
if( isDate(context, argc, argv, &JD) ){
int Y, M, D, h, m, s;
decomposeDate(JD, &Y, &M, &D, &s);
h = s/3600;
s -= h*3600;
m = s/60;
sqlite_set_result_int(context, m);
}
}
static void hourFunc(sqlite_func *context, int argc, const char **argv){
double JD;
if( isDate(context, argc, argv, &JD) ){
int Y, M, D, h, s;
decomposeDate(JD, &Y, &M, &D, &s);
h = s/3600;
sqlite_set_result_int(context, h);
}
}
#endif /* !defined(SQLITE_OMIT_DATETIME_FUNCS) */
/***************************************************************************/
/*
** This function registered all of the above C functions as SQL
** functions. This should be the only routine in this file with
@ -529,6 +836,19 @@ void sqliteRegisterBuiltinFunctions(sqlite *db){
{ "glob", 2, SQLITE_NUMERIC, globFunc },
{ "nullif", 2, SQLITE_ARGS, nullifFunc },
{ "sqlite_version",0,SQLITE_TEXT, versionFunc},
#ifndef SQLITE_OMIT_DATETIME_FUNCS
{ "julianday", -1, SQLITE_NUMERIC, juliandayFunc },
{ "timestamp", -1, SQLITE_TEXT, timestampFunc },
{ "time", -1, SQLITE_TEXT, timeFunc },
{ "date", -1, SQLITE_TEXT, dateFunc },
{ "year", -1, SQLITE_NUMERIC, yearFunc },
{ "month", -1, SQLITE_NUMERIC, monthFunc },
{ "dayofmonth",-1, SQLITE_NUMERIC, dayofmonthFunc },
{ "dayofweek", -1, SQLITE_NUMERIC, dayofweekFunc },
{ "hour", -1, SQLITE_NUMERIC, hourFunc },
{ "minute", -1, SQLITE_NUMERIC, minuteFunc },
{ "second", -1, SQLITE_NUMERIC, secondFunc },
#endif
#ifdef SQLITE_SOUNDEX
{ "soundex", 1, SQLITE_TEXT, soundexFunc},
#endif

View File

@ -1597,3 +1597,18 @@ char *sqliteOsFullPathname(const char *zRelative){
return zFull;
#endif
}
/*
** Find the current time (in Universal Coordinated Time). Write the
** current time and date as a Julian Day number into *prNow and
** return 0. Return 1 if the time and date cannot be found.
*/
int sqliteOsCurrentTime(double *prNow){
#if OS_UNIX
time_t t;
time(&t);
*prNow = t/86400.0 + 2440587.5;
return 0;
#endif
return 1;
}

View File

@ -171,6 +171,7 @@ int sqliteOsWriteLock(OsFile*);
int sqliteOsUnlock(OsFile*);
int sqliteOsRandomSeed(char*);
int sqliteOsSleep(int ms);
int sqliteOsCurrentTime(double*);
void sqliteOsEnterMutex(void);
void sqliteOsLeaveMutex(void);
char *sqliteOsFullPathname(const char*);

View File

@ -11,7 +11,7 @@
*************************************************************************
** Internal interface definitions for SQLite.
**
** @(#) $Id: sqliteInt.h,v 1.195 2003/07/30 12:34:12 drh Exp $
** @(#) $Id: sqliteInt.h,v 1.196 2003/08/09 21:32:28 drh Exp $
*/
#include "config.h"
#include "sqlite.h"
@ -87,6 +87,7 @@
/* #define SQLITE_OMIT_AUTHORIZATION 1 */
/* #define SQLITE_OMIT_INMEMORYDB 1 */
/* #define SQLITE_OMIT_VACUUM 1 */
/* #define SQLITE_OMIT_TIMEDATE_FUNCS 1 */
/*
** Integers of known sizes. These typedefs might change for architectures