rdelaage/postgresql
1
0
Fork 0
mirror of https://git.postgresql.org/git/postgresql.git synced 2024-09-09 12:39:28 +02:00
Code Issues Packages Projects Releases Wiki Activity
31edbadf4a
postgresql/src/include/utils/timestamp.h
Tom Lane 31edbadf4a Downgrade implicit casts to text to be assignment-only, except for the ones 
from the other string-category types; this eliminates a lot of surprising
interpretations that the parser could formerly make when there was no directly
applicable operator.

Create a general mechanism that supports casts to and from the standard string
types (text,varchar,bpchar) for *every* datatype, by invoking the datatype's
I/O functions.  These new casts are assignment-only in the to-string direction,
explicit-only in the other, and therefore should create no surprising behavior.
Remove a bunch of thereby-obsoleted datatype-specific casting functions.

The "general mechanism" is a new expression node type CoerceViaIO that can
actually convert between *any* two datatypes if their external text
representations are compatible.  This is more general than needed for the
immediate feature, but might be useful in plpgsql or other places in future.

This commit does nothing about the issue that applying the concatenation
operator || to non-text types will now fail, often with strange error messages
due to misinterpreting the operator as array concatenation.  Since it often
(not always) worked before, we should either make it succeed or at least give
a more user-friendly error; but details are still under debate.

Peter Eisentraut and Tom Lane
2007-06-05 21:31:09 +00:00

341 lines
12 KiB
C
Raw Blame History

/*-------------------------------------------------------------------------
*
* timestamp.h
* Definitions for the SQL92 "timestamp" and "interval" types.
*
* Portions Copyright (c) 1996-2007, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* $PostgreSQL: pgsql/src/include/utils/timestamp.h,v 1.70 2007/06/05 21:31:08 tgl Exp $
*
*-------------------------------------------------------------------------
*/
#ifndef TIMESTAMP_H
#define TIMESTAMP_H
#include <math.h>
#include <limits.h>
#include <float.h>
#include "fmgr.h"
#include "pgtime.h"
#ifdef HAVE_INT64_TIMESTAMP
#include "utils/int8.h"
#endif
/*
* Timestamp represents absolute time.
* Interval represents delta time. Keep track of months (and years), days,
* and time separately since the elapsed time spanned is unknown until
* instantiated relative to an absolute time.
*
* Note that Postgres uses "time interval" to mean a bounded interval,
* consisting of a beginning and ending time, not a time span - thomas 97/03/20
*/
#ifdef HAVE_INT64_TIMESTAMP
typedef int64 Timestamp;
typedef int64 TimestampTz;
#else
typedef double Timestamp;
typedef double TimestampTz;
#endif
typedef struct
{
#ifdef HAVE_INT64_TIMESTAMP
int64 time; /* all time units other than days, months and
* years */
#else
double time; /* all time units other than days, months and
* years */
#endif
int32 day; /* days, after time for alignment */
int32 month; /* months and years, after time for alignment */
} Interval;
#define MAX_TIMESTAMP_PRECISION 6
#define MAX_INTERVAL_PRECISION 6
/* in both timestamp.h and ecpg/dt.h */
#define DAYS_PER_YEAR 365.25 /* assumes leap year every four years */
#define MONTHS_PER_YEAR 12
/*
* DAYS_PER_MONTH is very imprecise. The more accurate value is
* 365.2425/12 = 30.436875, or '30 days 10:29:06'. Right now we only
* return an integral number of days, but someday perhaps we should
* also return a 'time' value to be used as well. ISO 8601 suggests
* 30 days.
*/
#define DAYS_PER_MONTH 30 /* assumes exactly 30 days per month */
#define HOURS_PER_DAY 24 /* assume no daylight savings time changes */
/*
* This doesn't adjust for uneven daylight savings time intervals or leap
* seconds, and it crudely estimates leap years. A more accurate value
* for days per years is 365.2422.
*/
#define SECS_PER_YEAR (36525 * 864) /* avoid floating-point computation */
#define SECS_PER_DAY 86400
#define SECS_PER_HOUR 3600
#define SECS_PER_MINUTE 60
#define MINS_PER_HOUR 60
#ifdef HAVE_INT64_TIMESTAMP
#define USECS_PER_DAY INT64CONST(86400000000)
#define USECS_PER_HOUR INT64CONST(3600000000)
#define USECS_PER_MINUTE INT64CONST(60000000)
#define USECS_PER_SEC INT64CONST(1000000)
#endif
/*
* Macros for fmgr-callable functions.
*
* For Timestamp, we make use of the same support routines as for int64
* or float8. Therefore Timestamp is pass-by-reference if and only if
* int64 or float8 is!
*/
#ifdef HAVE_INT64_TIMESTAMP
#define DatumGetTimestamp(X) ((Timestamp) DatumGetInt64(X))
#define DatumGetTimestampTz(X) ((TimestampTz) DatumGetInt64(X))
#define DatumGetIntervalP(X) ((Interval *) DatumGetPointer(X))
#define TimestampGetDatum(X) Int64GetDatum(X)
#define TimestampTzGetDatum(X) Int64GetDatum(X)
#define IntervalPGetDatum(X) PointerGetDatum(X)
#define PG_GETARG_TIMESTAMP(n) PG_GETARG_INT64(n)
#define PG_GETARG_TIMESTAMPTZ(n) PG_GETARG_INT64(n)
#define PG_GETARG_INTERVAL_P(n) DatumGetIntervalP(PG_GETARG_DATUM(n))
#define PG_RETURN_TIMESTAMP(x) PG_RETURN_INT64(x)
#define PG_RETURN_TIMESTAMPTZ(x) PG_RETURN_INT64(x)
#define PG_RETURN_INTERVAL_P(x) return IntervalPGetDatum(x)
#define DT_NOBEGIN (-INT64CONST(0x7fffffffffffffff) - 1)
#define DT_NOEND (INT64CONST(0x7fffffffffffffff))
#else
#define DatumGetTimestamp(X) ((Timestamp) DatumGetFloat8(X))
#define DatumGetTimestampTz(X) ((TimestampTz) DatumGetFloat8(X))
#define DatumGetIntervalP(X) ((Interval *) DatumGetPointer(X))
#define TimestampGetDatum(X) Float8GetDatum(X)
#define TimestampTzGetDatum(X) Float8GetDatum(X)
#define IntervalPGetDatum(X) PointerGetDatum(X)
#define PG_GETARG_TIMESTAMP(n) DatumGetTimestamp(PG_GETARG_DATUM(n))
#define PG_GETARG_TIMESTAMPTZ(n) DatumGetTimestampTz(PG_GETARG_DATUM(n))
#define PG_GETARG_INTERVAL_P(n) DatumGetIntervalP(PG_GETARG_DATUM(n))
#define PG_RETURN_TIMESTAMP(x) return TimestampGetDatum(x)
#define PG_RETURN_TIMESTAMPTZ(x) return TimestampTzGetDatum(x)
#define PG_RETURN_INTERVAL_P(x) return IntervalPGetDatum(x)
#ifdef HUGE_VAL
#define DT_NOBEGIN (-HUGE_VAL)
#define DT_NOEND (HUGE_VAL)
#else
#define DT_NOBEGIN (-DBL_MAX)
#define DT_NOEND (DBL_MAX)
#endif
#endif /* HAVE_INT64_TIMESTAMP */
#define TIMESTAMP_NOBEGIN(j) \
do {(j) = DT_NOBEGIN;} while (0)
#define TIMESTAMP_IS_NOBEGIN(j) ((j) == DT_NOBEGIN)
#define TIMESTAMP_NOEND(j) \
do {(j) = DT_NOEND;} while (0)
#define TIMESTAMP_IS_NOEND(j) ((j) == DT_NOEND)
#define TIMESTAMP_NOT_FINITE(j) (TIMESTAMP_IS_NOBEGIN(j) || TIMESTAMP_IS_NOEND(j))
#ifdef HAVE_INT64_TIMESTAMP
typedef int32 fsec_t;
#else
typedef double fsec_t;
#endif
/*
* Round off to MAX_TIMESTAMP_PRECISION decimal places.
* Note: this is also used for rounding off intervals.
*/
#define TS_PREC_INV 1000000.0
#define TSROUND(j) (rint(((double) (j)) * TS_PREC_INV) / TS_PREC_INV)
#define TIMESTAMP_MASK(b) (1 << (b))
#define INTERVAL_MASK(b) (1 << (b))
/* Macros to handle packing and unpacking the typmod field for intervals */
#define INTERVAL_FULL_RANGE (0x7FFF)
#define INTERVAL_RANGE_MASK (0x7FFF)
#define INTERVAL_FULL_PRECISION (0xFFFF)
#define INTERVAL_PRECISION_MASK (0xFFFF)
#define INTERVAL_TYPMOD(p,r) ((((r) & INTERVAL_RANGE_MASK) << 16) | ((p) & INTERVAL_PRECISION_MASK))
#define INTERVAL_PRECISION(t) ((t) & INTERVAL_PRECISION_MASK)
#define INTERVAL_RANGE(t) (((t) >> 16) & INTERVAL_RANGE_MASK)
#ifdef HAVE_INT64_TIMESTAMP
#define TimestampTzPlusMilliseconds(tz,ms) ((tz) + ((ms) * 1000))
#else
#define TimestampTzPlusMilliseconds(tz,ms) ((tz) + ((ms) / 1000.0))
#endif
/* Set at postmaster start */
extern TimestampTz PgStartTime;
/*
* timestamp.c prototypes
*/
extern Datum timestamp_in(PG_FUNCTION_ARGS);
extern Datum timestamp_out(PG_FUNCTION_ARGS);
extern Datum timestamp_recv(PG_FUNCTION_ARGS);
extern Datum timestamp_send(PG_FUNCTION_ARGS);
extern Datum timestamptypmodin(PG_FUNCTION_ARGS);
extern Datum timestamptypmodout(PG_FUNCTION_ARGS);
extern Datum timestamp_scale(PG_FUNCTION_ARGS);
extern Datum timestamp_eq(PG_FUNCTION_ARGS);
extern Datum timestamp_ne(PG_FUNCTION_ARGS);
extern Datum timestamp_lt(PG_FUNCTION_ARGS);
extern Datum timestamp_le(PG_FUNCTION_ARGS);
extern Datum timestamp_ge(PG_FUNCTION_ARGS);
extern Datum timestamp_gt(PG_FUNCTION_ARGS);
extern Datum timestamp_finite(PG_FUNCTION_ARGS);
extern Datum timestamp_cmp(PG_FUNCTION_ARGS);
extern Datum timestamp_smaller(PG_FUNCTION_ARGS);
extern Datum timestamp_larger(PG_FUNCTION_ARGS);
extern Datum timestamp_eq_timestamptz(PG_FUNCTION_ARGS);
extern Datum timestamp_ne_timestamptz(PG_FUNCTION_ARGS);
extern Datum timestamp_lt_timestamptz(PG_FUNCTION_ARGS);
extern Datum timestamp_le_timestamptz(PG_FUNCTION_ARGS);
extern Datum timestamp_gt_timestamptz(PG_FUNCTION_ARGS);
extern Datum timestamp_ge_timestamptz(PG_FUNCTION_ARGS);
extern Datum timestamp_cmp_timestamptz(PG_FUNCTION_ARGS);
extern Datum timestamptz_eq_timestamp(PG_FUNCTION_ARGS);
extern Datum timestamptz_ne_timestamp(PG_FUNCTION_ARGS);
extern Datum timestamptz_lt_timestamp(PG_FUNCTION_ARGS);
extern Datum timestamptz_le_timestamp(PG_FUNCTION_ARGS);
extern Datum timestamptz_gt_timestamp(PG_FUNCTION_ARGS);
extern Datum timestamptz_ge_timestamp(PG_FUNCTION_ARGS);
extern Datum timestamptz_cmp_timestamp(PG_FUNCTION_ARGS);
extern Datum interval_in(PG_FUNCTION_ARGS);
extern Datum interval_out(PG_FUNCTION_ARGS);
extern Datum interval_recv(PG_FUNCTION_ARGS);
extern Datum interval_send(PG_FUNCTION_ARGS);
extern Datum intervaltypmodin(PG_FUNCTION_ARGS);
extern Datum intervaltypmodout(PG_FUNCTION_ARGS);
extern Datum interval_scale(PG_FUNCTION_ARGS);
extern Datum interval_eq(PG_FUNCTION_ARGS);
extern Datum interval_ne(PG_FUNCTION_ARGS);
extern Datum interval_lt(PG_FUNCTION_ARGS);
extern Datum interval_le(PG_FUNCTION_ARGS);
extern Datum interval_ge(PG_FUNCTION_ARGS);
extern Datum interval_gt(PG_FUNCTION_ARGS);
extern Datum interval_finite(PG_FUNCTION_ARGS);
extern Datum interval_cmp(PG_FUNCTION_ARGS);
extern Datum interval_hash(PG_FUNCTION_ARGS);
extern Datum interval_smaller(PG_FUNCTION_ARGS);
extern Datum interval_larger(PG_FUNCTION_ARGS);
extern Datum interval_justify_interval(PG_FUNCTION_ARGS);
extern Datum interval_justify_hours(PG_FUNCTION_ARGS);
extern Datum interval_justify_days(PG_FUNCTION_ARGS);
extern Datum timestamp_trunc(PG_FUNCTION_ARGS);
extern Datum interval_trunc(PG_FUNCTION_ARGS);
extern Datum timestamp_part(PG_FUNCTION_ARGS);
extern Datum interval_part(PG_FUNCTION_ARGS);
extern Datum timestamp_zone(PG_FUNCTION_ARGS);
extern Datum timestamp_izone(PG_FUNCTION_ARGS);
extern Datum timestamp_timestamptz(PG_FUNCTION_ARGS);
extern Datum timestamptz_in(PG_FUNCTION_ARGS);
extern Datum timestamptz_out(PG_FUNCTION_ARGS);
extern Datum timestamptz_recv(PG_FUNCTION_ARGS);
extern Datum timestamptz_send(PG_FUNCTION_ARGS);
extern Datum timestamptztypmodin(PG_FUNCTION_ARGS);
extern Datum timestamptztypmodout(PG_FUNCTION_ARGS);
extern Datum timestamptz_scale(PG_FUNCTION_ARGS);
extern Datum timestamptz_timestamp(PG_FUNCTION_ARGS);
extern Datum timestamptz_zone(PG_FUNCTION_ARGS);
extern Datum timestamptz_izone(PG_FUNCTION_ARGS);
extern Datum timestamptz_timestamptz(PG_FUNCTION_ARGS);
extern Datum interval_um(PG_FUNCTION_ARGS);
extern Datum interval_pl(PG_FUNCTION_ARGS);
extern Datum interval_mi(PG_FUNCTION_ARGS);
extern Datum interval_mul(PG_FUNCTION_ARGS);
extern Datum mul_d_interval(PG_FUNCTION_ARGS);
extern Datum interval_div(PG_FUNCTION_ARGS);
extern Datum interval_accum(PG_FUNCTION_ARGS);
extern Datum interval_avg(PG_FUNCTION_ARGS);
extern Datum timestamp_mi(PG_FUNCTION_ARGS);
extern Datum timestamp_pl_interval(PG_FUNCTION_ARGS);
extern Datum timestamp_mi_interval(PG_FUNCTION_ARGS);
extern Datum timestamp_age(PG_FUNCTION_ARGS);
extern Datum overlaps_timestamp(PG_FUNCTION_ARGS);
extern Datum timestamptz_pl_interval(PG_FUNCTION_ARGS);
extern Datum timestamptz_mi_interval(PG_FUNCTION_ARGS);
extern Datum timestamptz_age(PG_FUNCTION_ARGS);
extern Datum timestamptz_trunc(PG_FUNCTION_ARGS);
extern Datum timestamptz_part(PG_FUNCTION_ARGS);
extern Datum now(PG_FUNCTION_ARGS);
extern Datum statement_timestamp(PG_FUNCTION_ARGS);
extern Datum clock_timestamp(PG_FUNCTION_ARGS);
extern Datum pgsql_postmaster_start_time(PG_FUNCTION_ARGS);
/* Internal routines (not fmgr-callable) */
extern TimestampTz GetCurrentTimestamp(void);
extern void TimestampDifference(TimestampTz start_time, TimestampTz stop_time,
long *secs, int *microsecs);
extern bool TimestampDifferenceExceeds(TimestampTz start_time,
TimestampTz stop_time,
int msec);
extern TimestampTz time_t_to_timestamptz(time_t tm);
extern time_t timestamptz_to_time_t(TimestampTz t);
extern const char *timestamptz_to_str(TimestampTz t);
extern int tm2timestamp(struct pg_tm * tm, fsec_t fsec, int *tzp, Timestamp *dt);
extern int timestamp2tm(Timestamp dt, int *tzp, struct pg_tm * tm,
fsec_t *fsec, char **tzn, pg_tz *attimezone);
extern void dt2time(Timestamp dt, int *hour, int *min, int *sec, fsec_t *fsec);
extern int interval2tm(Interval span, struct pg_tm * tm, fsec_t *fsec);
extern int tm2interval(struct pg_tm * tm, fsec_t fsec, Interval *span);
extern Timestamp SetEpochTimestamp(void);
extern void GetEpochTime(struct pg_tm * tm);
extern int timestamp_cmp_internal(Timestamp dt1, Timestamp dt2);
/* timestamp comparison works for timestamptz also */
#define timestamptz_cmp_internal(dt1,dt2) timestamp_cmp_internal(dt1, dt2)
extern int isoweek2j(int year, int week);
extern void isoweek2date(int woy, int *year, int *mon, int *mday);
extern void isoweekdate2date(int isoweek, int isowday, int *year, int *mon, int *mday);
extern int date2isoweek(int year, int mon, int mday);
extern int date2isoyear(int year, int mon, int mday);
extern int date2isoyearday(int year, int mon, int mday);
#endif /* TIMESTAMP_H */
Reference in New Issue View Git Blame Copy Permalink