|
15 | 15 | * |
16 | 16 | * |
17 | 17 | * IDENTIFICATION |
18 | | - * $Header: /cvsroot/pgsql/src/backend/utils/adt/selfuncs.c,v 1.56 2000/02/16 00:59:27 tgl Exp $ |
| 18 | + * $Header: /cvsroot/pgsql/src/backend/utils/adt/selfuncs.c,v 1.57 2000/02/26 23:03:12 tgl Exp $ |
19 | 19 | * |
20 | 20 | *------------------------------------------------------------------------- |
21 | 21 | */ |
@@ -470,9 +470,19 @@ scalargtjoinsel(Oid opid, |
470 | 470 | * Returns "true" if successful. |
471 | 471 | * |
472 | 472 | * All numeric datatypes are simply converted to their equivalent |
473 | | - * "double" values. String datatypes are converted to a crude scale |
474 | | - * using their first character (only if it is in the ASCII range, |
475 | | - * to try to avoid problems with non-ASCII collating sequences). |
| 473 | + * "double" values. |
| 474 | + * |
| 475 | + * String datatypes are converted to a crude scale using their first character |
| 476 | + * (only if it is in the ASCII range, to try to avoid problems with non-ASCII |
| 477 | + * collating sequences). |
| 478 | + * |
| 479 | + * The several datatypes representing absolute times are all converted |
| 480 | + * to Timestamp, which is actually a double, and then we just use that |
| 481 | + * double value. Note this will give bad results for the various "special" |
| 482 | + * values of Timestamp --- what can we do with those? |
| 483 | + * |
| 484 | + * The several datatypes representing relative times (intervals) are all |
| 485 | + * converted to measurements expressed in seconds. |
476 | 486 | */ |
477 | 487 | bool |
478 | 488 | convert_to_scalar(Datumvalue,Oidtypid, |
@@ -551,12 +561,63 @@ convert_to_scalar(Datum value, Oid typid, |
551 | 561 | break; |
552 | 562 | } |
553 | 563 |
|
| 564 | +/* |
| 565 | + * Built-in absolute-time types |
| 566 | + */ |
| 567 | +caseTIMESTAMPOID: |
| 568 | +*scaleval=* ((Timestamp*)DatumGetPointer(value)); |
| 569 | +return true; |
| 570 | +caseABSTIMEOID: |
| 571 | +*scaleval=*abstime_timestamp(value); |
| 572 | +return true; |
| 573 | +caseDATEOID: |
| 574 | +*scaleval=*date_timestamp(value); |
| 575 | +return true; |
| 576 | + |
| 577 | +/* |
| 578 | + * Built-in relative-time types |
| 579 | + */ |
| 580 | +caseINTERVALOID: |
| 581 | +{ |
| 582 | +Interval*interval= (Interval*)DatumGetPointer(value); |
| 583 | + |
| 584 | +/* |
| 585 | + * Convert the month part of Interval to days using assumed |
| 586 | + * average month length of 365.25/12.0 days. Not too accurate, |
| 587 | + * but plenty good enough for our purposes. |
| 588 | + */ |
| 589 | +*scaleval=interval->time+ |
| 590 | +interval->month* (365.25/12.0*24.0*60.0*60.0); |
| 591 | +return true; |
| 592 | +} |
| 593 | +caseRELTIMEOID: |
| 594 | +*scaleval= (RelativeTime)DatumGetInt32(value); |
| 595 | +return true; |
| 596 | +caseTINTERVALOID: |
| 597 | +{ |
| 598 | +TimeIntervalinterval= (TimeInterval)DatumGetPointer(value); |
| 599 | + |
| 600 | +if (interval->status!=0) |
| 601 | +{ |
| 602 | +*scaleval=interval->data[1]-interval->data[0]; |
| 603 | +return true; |
| 604 | +} |
| 605 | +break; |
| 606 | +} |
| 607 | +caseTIMEOID: |
| 608 | +*scaleval=* ((TimeADT*)DatumGetPointer(value)); |
| 609 | +return true; |
| 610 | + |
554 | 611 | default: |
555 | 612 | { |
556 | 613 | /* |
557 | 614 | * See whether there is a registered type-conversion function, |
558 | 615 | * namely a procedure named "float8" with the right signature. |
559 | 616 | * If so, assume we can convert the value to the numeric scale. |
| 617 | + * |
| 618 | + * NOTE: there are no such procedures in the standard distribution, |
| 619 | + * except with argument types that we already dealt with above. |
| 620 | + * This code is just here as an escape for user-defined types. |
560 | 621 | */ |
561 | 622 | Oidoid_array[FUNC_MAX_ARGS]; |
562 | 623 | HeapTupleftup; |
|