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Revised date/time functions - now broken out into a separate source file.
See the DateAndTimeFunctions wiki page for additional information. (CVS 1116) FossilOrigin-Name: 68ef9b45bd3abdedf3721011ad0fb22e8735e721
This commit is contained in:
drh
773
src/date.c
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773
src/date.c
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@@ -0,0 +1,773 @@
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/*
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** 2003 October 31
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**
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** The author disclaims copyright to this source code. In place of
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** a legal notice, here is a blessing:
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**
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** May you do good and not evil.
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** May you find forgiveness for yourself and forgive others.
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** May you share freely, never taking more than you give.
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**
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*************************************************************************
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** This file contains the C functions that implement date and time
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** functions for SQLite.
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**
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** There is only one exported symbol in this file - the function
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** sqliteRegisterDateTimeFunctions() 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: date.c,v 1.1 2003/11/01 01:53:54 drh Exp $
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**
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** NOTES:
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**
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** SQLite processes all times and dates as Julian Day numbers. The
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** dates and times are stored as the number of days since noon
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** in Greenwich on November 24, 4714 B.C. according to the Gregorian
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** calendar system.
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**
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** 1970-01-01 00:00:00 is JD 2440587.5
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** 2000-01-01 00:00:00 is JD 2451544.5
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**
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** This implemention requires years to be expressed as a 4-digit number
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** which means that only dates between 0000-01-01 and 9999-12-31 can
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** be represented, even though julian day numbers allow a much wider
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** range of dates.
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**
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** The Gregorian calendar system is used for all dates and times,
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** even those that predate the Gregorian calendar. Historians usually
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** use the Julian calendar for dates prior to 1582-10-15 and for some
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** dates afterwards, depending on locale. Beware of this difference.
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**
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** The conversion algorithms are implemented based on descriptions
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** in the following text:
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**
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** Jean Meeus
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** Astronomical Algorithms, 2nd Edition, 1998
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** ISBM 0-943396-61-1
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** Willmann-Bell, Inc
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** Richmond, Virginia (USA)
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*/
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#ifndef SQLITE_OMIT_DATETIME_FUNCS
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#include <ctype.h>
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#include <stdlib.h>
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#include <assert.h>
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#include "sqliteInt.h"
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#include "os.h"
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/*
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** A structure for holding a single date and time.
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*/
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typedef struct DateTime DateTime;
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struct DateTime {
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double rJD; /* The julian day number */
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int Y, M, D; /* Year, month, and day */
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int h, m; /* Hour and minutes */
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int tz; /* Timezone offset in minutes */
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double s; /* Seconds */
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char validYMD; /* True if Y,M,D are valid */
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char validHMS; /* True if h,m,s are valid */
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char validJD; /* True if rJD is valid */
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char validTZ; /* True if tz is valid */
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};
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/*
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** Convert N digits from zDate into an integer. Return
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** -1 if zDate does not begin with N digits.
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*/
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static int getDigits(const char *zDate, int N){
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int val = 0;
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while( N-- ){
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if( !isdigit(*zDate) ) return -1;
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val = val*10 + *zDate - '0';
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zDate++;
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}
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return val;
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}
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/*
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** Read text from z[] and convert into a floating point number. Return
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** the number of digits converted.
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*/
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static int getValue(const char *z, double *pR){
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double r = 0.0;
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double rDivide = 1.0;
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int isNeg = 0;
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int nChar = 0;
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if( *z=='+' ){
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z++;
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nChar++;
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}else if( *z=='-' ){
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z++;
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isNeg = 1;
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nChar++;
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}
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if( !isdigit(*z) ) return 0;
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while( isdigit(*z) ){
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r = r*10.0 + *z - '0';
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nChar++;
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z++;
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}
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if( *z=='.' && isdigit(z[1]) ){
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z++;
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nChar++;
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while( isdigit(*z) ){
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r = r*10.0 + *z - '0';
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rDivide *= 10.0;
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nChar++;
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z++;
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}
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r /= rDivide;
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}
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if( *z!=0 && !isspace(*z) ) return 0;
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*pR = isNeg ? -r : r;
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return nChar;
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}
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/*
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** Parse a timezone extension on the end of a date-time.
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** The extension is of the form:
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**
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** (+/-)HH:MM
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**
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** If the parse is successful, write the number of minutes
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** of change in *pnMin and return 0. If a parser error occurs,
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** return 0.
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**
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** A missing specifier is not considered an error.
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*/
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static int parseTimezone(const char *zDate, DateTime *p){
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int sgn = 0;
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int nHr, nMn;
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while( isspace(*zDate) ){ zDate++; }
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p->tz = 0;
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if( *zDate=='-' ){
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sgn = -1;
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}else if( *zDate=='+' ){
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sgn = +1;
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}else{
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return *zDate!=0;
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}
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zDate++;
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nHr = getDigits(zDate, 2);
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if( nHr<0 || nHr>14 ) return 1;
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zDate += 2;
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if( zDate[0]!=':' ) return 1;
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zDate++;
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nMn = getDigits(zDate, 2);
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if( nMn<0 || nMn>59 ) return 1;
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zDate += 2;
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p->tz = sgn*(nMn + nHr*60);
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while( isspace(*zDate) ){ zDate++; }
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return *zDate!=0;
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}
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/*
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** Parse times of the form HH:MM or HH:MM:SS or HH:MM:SS.FFFF.
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** The HH, MM, and SS must each be exactly 2 digits. The
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** fractional seconds FFFF can be one or more digits.
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**
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** Return 1 if there is a parsing error and 0 on success.
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*/
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static int parseHhMmSs(const char *zDate, DateTime *p){
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int h, m, s;
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double ms = 0.0;
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h = getDigits(zDate, 2);
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if( h<0 || zDate[2]!=':' ) return 1;
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zDate += 3;
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m = getDigits(zDate, 2);
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if( m<0 || m>59 ) return 1;
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zDate += 2;
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if( *zDate==':' ){
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s = getDigits(&zDate[1], 2);
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if( s<0 || s>59 ) return 1;
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zDate += 3;
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if( *zDate=='.' && isdigit(zDate[1]) ){
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double rScale = 1.0;
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zDate++;
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while( isdigit(*zDate) ){
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ms = ms*10.0 + *zDate - '0';
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rScale *= 10.0;
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zDate++;
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}
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ms /= rScale;
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}
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}else{
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s = 0;
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}
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p->validJD = 0;
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p->validHMS = 1;
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p->h = h;
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p->m = m;
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p->s = s + ms;
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if( parseTimezone(zDate, p) ) return 1;
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p->validTZ = p->tz!=0;
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return 0;
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}
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/*
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** Convert from YYYY-MM-DD HH:MM:SS to julian day. We always assume
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** that the YYYY-MM-DD is according to the Gregorian calendar.
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**
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** Reference: Meeus page 61
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*/
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static void computeJD(DateTime *p){
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int Y, M, D, A, B, X1, X2;
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if( p->validJD ) return;
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if( p->validYMD ){
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Y = p->Y;
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M = p->M;
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D = p->D;
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}else{
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Y = 2000;
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M = 1;
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D = 1;
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}
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if( M<=2 ){
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Y--;
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M += 12;
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}
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A = Y/100;
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B = 2 - A + (A/4);
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X1 = 365.25*(Y+4716);
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X2 = 30.6001*(M+1);
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p->rJD = X1 + X2 + D + B - 1524.5;
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p->validJD = 1;
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p->validYMD = 0;
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if( p->validHMS ){
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p->rJD += (p->h*3600.0 + p->m*60.0 + p->s)/86400.0;
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if( p->validTZ ){
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p->rJD += p->tz*60/86400.0;
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p->validHMS = 0;
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p->validTZ = 0;
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}
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}
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}
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/*
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** Parse dates of the form
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**
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** YYYY-MM-DD HH:MM:SS.FFF
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** YYYY-MM-DD HH:MM:SS
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** YYYY-MM-DD HH:MM
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** YYYY-MM-DD
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**
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** Write the result into the DateTime structure and return 0
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** on success and 1 if the input string is not a well-formed
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** date.
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*/
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static int parseYyyyMmDd(const char *zDate, DateTime *p){
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int Y, M, D;
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Y = getDigits(zDate, 4);
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if( Y<0 || zDate[4]!='-' ) return 1;
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zDate += 5;
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M = getDigits(zDate, 2);
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if( M<=0 || M>12 || zDate[2]!='-' ) return 1;
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zDate += 3;
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D = getDigits(zDate, 2);
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if( D<=0 || D>31 ) return 1;
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zDate += 2;
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while( isspace(*zDate) ){ zDate++; }
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if( isdigit(*zDate) ){
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if( parseHhMmSs(zDate, p) ) return 1;
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}else if( *zDate==0 ){
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p->validHMS = 0;
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}else{
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return 1;
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}
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p->validJD = 0;
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p->validYMD = 1;
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p->Y = Y;
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p->M = M;
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p->D = D;
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if( p->validTZ ){
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computeJD(p);
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}
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return 0;
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}
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/*
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** Attempt to parse the given string into a Julian Day Number. Return
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** the number of errors.
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**
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** The following are acceptable forms for the input string:
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**
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** YYYY-MM-DD HH:MM:SS.FFF +/-HH:MM
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** DDDD.DD
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** now
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**
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** In the first form, the +/-HH:MM is always optional. The fractional
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** seconds extension (the ".FFF") is optional. The seconds portion
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** (":SS.FFF") is option. The year and date can be omitted as long
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** as there is a time string. The time string can be omitted as long
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** as there is a year and date.
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*/
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static int parseDateOrTime(const char *zDate, DateTime *p){
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int i;
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memset(p, 0, sizeof(*p));
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for(i=0; isdigit(zDate[i]); i++){}
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if( i==4 && zDate[i]=='-' ){
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return parseYyyyMmDd(zDate, p);
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}else if( i==2 && zDate[i]==':' ){
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return parseHhMmSs(zDate, p);
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return 0;
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}else if( i==0 && sqliteStrICmp(zDate,"now")==0 ){
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double r;
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if( sqliteOsCurrentTime(&r)==0 ){
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p->rJD = r;
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p->validJD = 1;
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return 0;
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}
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return 1;
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}else if( sqliteIsNumber(zDate) ){
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p->rJD = atof(zDate);
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p->validJD = 1;
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return 0;
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}
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return 1;
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}
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/*
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** Compute the Year, Month, and Day from the julian day number.
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*/
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static void computeYMD(DateTime *p){
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int Z, A, B, C, D, E, X1;
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if( p->validYMD ) return;
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Z = p->rJD + 0.5;
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A = (Z - 1867216.25)/36524.25;
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A = Z + 1 + A - (A/4);
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B = A + 1524;
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C = (B - 122.1)/365.25;
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D = 365.25*C;
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E = (B-D)/30.6001;
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X1 = 30.6001*E;
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p->D = B - D - X1;
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p->M = E<14 ? E-1 : E-13;
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p->Y = p->M>2 ? C - 4716 : C - 4715;
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p->validYMD = 1;
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}
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/*
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** Compute the Hour, Minute, and Seconds from the julian day number.
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*/
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static void computeHMS(DateTime *p){
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int Z, s;
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if( p->validHMS ) return;
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Z = p->rJD + 0.5;
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s = (p->rJD + 0.5 - Z)*86400000.0 + 0.5;
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p->s = 0.001*s;
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s = p->s;
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p->s -= s;
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p->h = s/3600;
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s -= p->h*3600;
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p->m = s/60;
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p->s += s - p->m*60;
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p->validHMS = 1;
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}
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|
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/*
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** Process a modifier to a date-time stamp. The modifiers are
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** as follows:
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||||
**
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** NNN days
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** NNN hours
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** NNN minutes
|
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** NNN.NNNN seconds
|
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** NNN months
|
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** NNN years
|
||||
** start of month
|
||||
** start of year
|
||||
** start of week
|
||||
** start of day
|
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** weekday N
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** unixepoch
|
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**
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||||
** Return 0 on success and 1 if there is any kind of error.
|
||||
*/
|
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static int parseModifier(const char *zMod, DateTime *p){
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int rc = 1;
|
||||
int n;
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double r;
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char z[30];
|
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for(n=0; n<sizeof(z)-1; n++){
|
||||
z[n] = tolower(zMod[n]);
|
||||
}
|
||||
z[n] = 0;
|
||||
switch( z[0] ){
|
||||
case 'u': {
|
||||
/*
|
||||
** unixepoch
|
||||
**
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||||
** Treat the current value of p->rJD as the number of
|
||||
** seconds since 1970. Convert to a real julian day number.
|
||||
*/
|
||||
if( strcmp(z, "unixepoch")==0 && p->validJD ){
|
||||
p->rJD = p->rJD/86400.0 + 2440587.5;
|
||||
p->validYMD = 0;
|
||||
p->validHMS = 0;
|
||||
p->validTZ = 0;
|
||||
rc = 0;
|
||||
}
|
||||
break;
|
||||
}
|
||||
case 'w': {
|
||||
/*
|
||||
** weekday N
|
||||
**
|
||||
** Move the date to the beginning of the next occurrance of
|
||||
** weekday N where 0==Sunday, 1==Monday, and so forth. If the
|
||||
** date is already on the appropriate weekday, this is equivalent
|
||||
** to "start of day".
|
||||
*/
|
||||
if( strncmp(z, "weekday ", 8)==0 && getValue(&z[8],&r)>0
|
||||
&& (n=r)==r && n>=0 && r<7 ){
|
||||
int Z;
|
||||
computeYMD(p);
|
||||
p->validHMS = 0;
|
||||
p->validTZ = 0;
|
||||
p->validJD = 0;
|
||||
computeJD(p);
|
||||
Z = p->rJD + 1.5;
|
||||
Z %= 7;
|
||||
if( Z>n ) Z -= 7;
|
||||
p->rJD += n - Z;
|
||||
p->validYMD = 0;
|
||||
p->validHMS = 0;
|
||||
rc = 0;
|
||||
}
|
||||
break;
|
||||
}
|
||||
case 's': {
|
||||
/*
|
||||
** start of TTTTT
|
||||
**
|
||||
** Move the date backwards to the beginning of the current day,
|
||||
** or month or year.
|
||||
*/
|
||||
if( strncmp(z, "start of ", 9)!=0 ) break;
|
||||
zMod = &z[9];
|
||||
computeYMD(p);
|
||||
p->validHMS = 1;
|
||||
p->h = p->m = 0;
|
||||
p->s = 0.0;
|
||||
p->validTZ = 0;
|
||||
p->validJD = 0;
|
||||
if( strcmp(zMod,"month")==0 ){
|
||||
p->D = 1;
|
||||
rc = 0;
|
||||
}else if( strcmp(zMod,"year")==0 ){
|
||||
computeYMD(p);
|
||||
p->M = 1;
|
||||
p->D = 1;
|
||||
rc = 0;
|
||||
}else if( strcmp(zMod,"day")==0 ){
|
||||
rc = 0;
|
||||
}
|
||||
break;
|
||||
}
|
||||
case '+':
|
||||
case '-':
|
||||
case '0':
|
||||
case '1':
|
||||
case '2':
|
||||
case '3':
|
||||
case '4':
|
||||
case '5':
|
||||
case '6':
|
||||
case '7':
|
||||
case '8':
|
||||
case '9': {
|
||||
n = getValue(z, &r);
|
||||
if( n<=0 ) break;
|
||||
zMod = &z[n];
|
||||
while( isspace(zMod[0]) ) zMod++;
|
||||
n = strlen(zMod);
|
||||
if( n>10 || n<3 ) break;
|
||||
strcpy(z, zMod);
|
||||
if( z[n-1]=='s' ){ z[n-1] = 0; n--; }
|
||||
computeJD(p);
|
||||
rc = 0;
|
||||
if( n==3 && strcmp(z,"day")==0 ){
|
||||
p->rJD += r;
|
||||
}else if( n==4 && strcmp(z,"hour")==0 ){
|
||||
computeJD(p);
|
||||
p->rJD += r/24.0;
|
||||
}else if( n==6 && strcmp(z,"minute")==0 ){
|
||||
computeJD(p);
|
||||
p->rJD += r/(24.0*60.0);
|
||||
}else if( n==6 && strcmp(z,"second")==0 ){
|
||||
computeJD(p);
|
||||
p->rJD += r/(24.0*60.0*60.0);
|
||||
}else if( n==5 && strcmp(z,"month")==0 ){
|
||||
int x, y;
|
||||
computeYMD(p);
|
||||
p->M += r;
|
||||
x = p->M>0 ? (p->M-1)/12 : (p->M-12)/12;
|
||||
p->Y += x;
|
||||
p->M -= x*12;
|
||||
p->validJD = 0;
|
||||
computeJD(p);
|
||||
y = r;
|
||||
if( y!=r ){
|
||||
p->rJD += (r - y)*30.0;
|
||||
}
|
||||
}else if( n==4 && strcmp(z,"year")==0 ){
|
||||
computeYMD(p);
|
||||
p->Y += r;
|
||||
p->validJD = 0;
|
||||
computeJD(p);
|
||||
}else{
|
||||
rc = 1;
|
||||
}
|
||||
p->validYMD = 0;
|
||||
p->validHMS = 0;
|
||||
p->validTZ = 0;
|
||||
break;
|
||||
}
|
||||
default: {
|
||||
break;
|
||||
}
|
||||
}
|
||||
return rc;
|
||||
}
|
||||
|
||||
/*
|
||||
** Process time function arguments. argv[0] is a date-time stamp.
|
||||
** argv[1] and following are modifiers. Parse them all and write
|
||||
** the resulting time into the DateTime structure p. Return 0
|
||||
** on success and 1 if there are any errors.
|
||||
*/
|
||||
static int isDate(int argc, const char **argv, DateTime *p){
|
||||
int i;
|
||||
if( argc==0 ) return 1;
|
||||
if( parseDateOrTime(argv[0], p) ) return 1;
|
||||
for(i=1; i<argc; i++){
|
||||
if( parseModifier(argv[i], p) ) return 1;
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
|
||||
/*
|
||||
** The following routines implement the various date and time functions
|
||||
** of SQLite.
|
||||
*/
|
||||
|
||||
/*
|
||||
** julianday( TIMESTRING, MOD, MOD, ...)
|
||||
**
|
||||
** Return the julian day number of the date specified in the arguments
|
||||
*/
|
||||
static void juliandayFunc(sqlite_func *context, int argc, const char **argv){
|
||||
DateTime x;
|
||||
if( isDate(argc, argv, &x)==0 ){
|
||||
computeJD(&x);
|
||||
sqlite_set_result_double(context, x.rJD);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
** datetime( TIMESTRING, MOD, MOD, ...)
|
||||
**
|
||||
** Return YYYY-MM-DD HH:MM:SS
|
||||
*/
|
||||
static void datetimeFunc(sqlite_func *context, int argc, const char **argv){
|
||||
DateTime x;
|
||||
if( isDate(argc, argv, &x)==0 ){
|
||||
char zBuf[100];
|
||||
computeYMD(&x);
|
||||
computeHMS(&x);
|
||||
sprintf(zBuf, "%04d-%02d-%02d %02d:%02d:%02d",x.Y, x.M, x.D, x.h, x.m,
|
||||
(int)(x.s));
|
||||
sqlite_set_result_string(context, zBuf, -1);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
** time( TIMESTRING, MOD, MOD, ...)
|
||||
**
|
||||
** Return HH:MM:SS
|
||||
*/
|
||||
static void timeFunc(sqlite_func *context, int argc, const char **argv){
|
||||
DateTime x;
|
||||
if( isDate(argc, argv, &x)==0 ){
|
||||
char zBuf[100];
|
||||
computeHMS(&x);
|
||||
sprintf(zBuf, "%02d:%02d:%02d", x.h, x.m, (int)x.s);
|
||||
sqlite_set_result_string(context, zBuf, -1);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
** date( TIMESTRING, MOD, MOD, ...)
|
||||
**
|
||||
** Return YYYY-MM-DD
|
||||
*/
|
||||
static void dateFunc(sqlite_func *context, int argc, const char **argv){
|
||||
DateTime x;
|
||||
if( isDate(argc, argv, &x)==0 ){
|
||||
char zBuf[100];
|
||||
computeYMD(&x);
|
||||
sprintf(zBuf, "%04d-%02d-%02d", x.Y, x.M, x.D);
|
||||
sqlite_set_result_string(context, zBuf, -1);
|
||||
}
|
||||
}
|
||||
|
||||
/*
|
||||
** strftime( FORMAT, TIMESTRING, MOD, MOD, ...)
|
||||
**
|
||||
** Return a string described by FORMAT. Conversions as follows:
|
||||
**
|
||||
** %d day of month
|
||||
** %f ** fractional seconds SS.SSS
|
||||
** %H hour 00-24
|
||||
** %j day of year 000-366
|
||||
** %J ** Julian day number
|
||||
** %m month 01-12
|
||||
** %M minute 00-59
|
||||
** %s seconds since 1970-01-01
|
||||
** %S seconds 00-59
|
||||
** %w day of week 0-6 sunday==0
|
||||
** %W week of year 00-53
|
||||
** %Y year 0000-9999
|
||||
** %% %
|
||||
*/
|
||||
static void strftimeFunc(sqlite_func *context, int argc, const char **argv){
|
||||
DateTime x;
|
||||
int n, i, j;
|
||||
char *z;
|
||||
const char *zFmt = argv[0];
|
||||
char zBuf[100];
|
||||
if( isDate(argc-1, argv+1, &x) ) return;
|
||||
for(i=0, n=1; zFmt[i]; i++, n++){
|
||||
if( zFmt[i]=='%' ){
|
||||
switch( zFmt[i+1] ){
|
||||
case 'd':
|
||||
case 'H':
|
||||
case 'm':
|
||||
case 'M':
|
||||
case 'S':
|
||||
case 'W':
|
||||
n++;
|
||||
/* fall thru */
|
||||
case 'w':
|
||||
case '%':
|
||||
break;
|
||||
case 'f':
|
||||
n += 8;
|
||||
break;
|
||||
case 'j':
|
||||
n += 3;
|
||||
break;
|
||||
case 'Y':
|
||||
n += 8;
|
||||
break;
|
||||
case 's':
|
||||
case 'J':
|
||||
n += 50;
|
||||
break;
|
||||
default:
|
||||
return; /* ERROR. return a NULL */
|
||||
}
|
||||
i++;
|
||||
}
|
||||
}
|
||||
if( n<sizeof(zBuf) ){
|
||||
z = zBuf;
|
||||
}else{
|
||||
z = sqliteMalloc( n );
|
||||
if( z==0 ) return;
|
||||
}
|
||||
computeJD(&x);
|
||||
computeYMD(&x);
|
||||
computeHMS(&x);
|
||||
for(i=j=0; zFmt[i]; i++){
|
||||
if( zFmt[i]!='%' ){
|
||||
z[j++] = zFmt[i];
|
||||
}else{
|
||||
i++;
|
||||
switch( zFmt[i] ){
|
||||
case 'd': sprintf(&z[j],"%02d",x.D); j+=2; break;
|
||||
case 'f': {
|
||||
int s = x.s;
|
||||
int ms = (x.s - s)*1000.0;
|
||||
sprintf(&z[j],"%02d.%03d",s,ms);
|
||||
j += strlen(&z[j]);
|
||||
break;
|
||||
}
|
||||
case 'H': sprintf(&z[j],"%02d",x.h); j+=2; break;
|
||||
case 'W': /* Fall thru */
|
||||
case 'j': {
|
||||
int n;
|
||||
DateTime y = x;
|
||||
y.validJD = 0;
|
||||
y.M = 1;
|
||||
y.D = 1;
|
||||
computeJD(&y);
|
||||
n = x.rJD - y.rJD + 1;
|
||||
if( zFmt[i]=='W' ){
|
||||
sprintf(&z[j],"%02d",(n+6)/7);
|
||||
j += 2;
|
||||
}else{
|
||||
sprintf(&z[j],"%03d",n);
|
||||
j += 3;
|
||||
}
|
||||
break;
|
||||
}
|
||||
case 'J': sprintf(&z[j],"%.16g",x.rJD); j+=strlen(&z[j]); break;
|
||||
case 'm': sprintf(&z[j],"%02d",x.M); j+=2; break;
|
||||
case 'M': sprintf(&z[j],"%02d",x.m); j+=2; break;
|
||||
case 's': {
|
||||
sprintf(&z[j],"%d",(int)((x.rJD-2440587.5)*86400.0));
|
||||
j += strlen(&z[j]);
|
||||
break;
|
||||
}
|
||||
case 'S': sprintf(&z[j],"%02d",(int)x.s); j+=2; break;
|
||||
case 'w': z[j++] = (((int)(x.rJD+1.5)) % 7) + '0'; break;
|
||||
case 'Y': sprintf(&z[j],"%04d",x.Y); j+=strlen(&z[j]); break;
|
||||
case '%': z[j++] = '%'; break;
|
||||
}
|
||||
}
|
||||
}
|
||||
z[j] = 0;
|
||||
sqlite_set_result_string(context, z, -1);
|
||||
if( z!=zBuf ){
|
||||
sqliteFree(z);
|
||||
}
|
||||
}
|
||||
|
||||
|
||||
#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
|
||||
** external linkage.
|
||||
*/
|
||||
void sqliteRegisterDateTimeFunctions(sqlite *db){
|
||||
static struct {
|
||||
char *zName;
|
||||
int nArg;
|
||||
int dataType;
|
||||
void (*xFunc)(sqlite_func*,int,const char**);
|
||||
} aFuncs[] = {
|
||||
#ifndef SQLITE_OMIT_DATETIME_FUNCS
|
||||
{ "julianday", -1, SQLITE_NUMERIC, juliandayFunc },
|
||||
{ "date", -1, SQLITE_TEXT, dateFunc },
|
||||
{ "time", 1, SQLITE_TEXT, timeFunc },
|
||||
{ "datetime", -1, SQLITE_TEXT, datetimeFunc },
|
||||
{ "strftime", -1, SQLITE_TEXT, strftimeFunc },
|
||||
#endif
|
||||
};
|
||||
int i;
|
||||
|
||||
for(i=0; i<sizeof(aFuncs)/sizeof(aFuncs[0]); i++){
|
||||
sqlite_create_function(db, aFuncs[i].zName,
|
||||
aFuncs[i].nArg, aFuncs[i].xFunc, 0);
|
||||
if( aFuncs[i].xFunc ){
|
||||
sqlite_function_type(db, aFuncs[i].zName, aFuncs[i].dataType);
|
||||
}
|
||||
}
|
||||
}
|
||||
Reference in New Issue
Block a user