Line data    Source code

       1             : /*-------------------------------------------------------------------------
       2             :  *
       3             :  * scankey.c
       4             :  *    scan key support code
       5             :  *
       6             :  * Portions Copyright (c) 1996-2017, PostgreSQL Global Development Group
       7             :  * Portions Copyright (c) 1994, Regents of the University of California
       8             :  *
       9             :  *
      10             :  * IDENTIFICATION
      11             :  *    src/backend/access/common/scankey.c
      12             :  *
      13             :  *-------------------------------------------------------------------------
      14             :  */
      15             : #include "postgres.h"
      16             : 
      17             : #include "access/skey.h"
      18             : #include "catalog/pg_collation.h"
      19             : 
      20             : 
      21             : /*
      22             :  * ScanKeyEntryInitialize
      23             :  *      Initializes a scan key entry given all the field values.
      24             :  *      The target procedure is specified by OID (but can be invalid
      25             :  *      if SK_SEARCHNULL or SK_SEARCHNOTNULL is set).
      26             :  *
      27             :  * Note: CurrentMemoryContext at call should be as long-lived as the ScanKey
      28             :  * itself, because that's what will be used for any subsidiary info attached
      29             :  * to the ScanKey's FmgrInfo record.
      30             :  */
      31             : void
      32       13678 : ScanKeyEntryInitialize(ScanKey entry,
      33             :                        int flags,
      34             :                        AttrNumber attributeNumber,
      35             :                        StrategyNumber strategy,
      36             :                        Oid subtype,
      37             :                        Oid collation,
      38             :                        RegProcedure procedure,
      39             :                        Datum argument)
      40             : {
      41       13678 :     entry->sk_flags = flags;
      42       13678 :     entry->sk_attno = attributeNumber;
      43       13678 :     entry->sk_strategy = strategy;
      44       13678 :     entry->sk_subtype = subtype;
      45       13678 :     entry->sk_collation = collation;
      46       13678 :     entry->sk_argument = argument;
      47       13678 :     if (RegProcedureIsValid(procedure))
      48             :     {
      49       13001 :         fmgr_info(procedure, &entry->sk_func);
      50             :     }
      51             :     else
      52             :     {
      53         677 :         Assert(flags & (SK_SEARCHNULL | SK_SEARCHNOTNULL));
      54         677 :         MemSet(&entry->sk_func, 0, sizeof(entry->sk_func));
      55             :     }
      56       13678 : }
      57             : 
      58             : /*
      59             :  * ScanKeyInit
      60             :  *      Shorthand version of ScanKeyEntryInitialize: flags and subtype
      61             :  *      are assumed to be zero (the usual value), and collation is defaulted.
      62             :  *
      63             :  * This is the recommended version for hardwired lookups in system catalogs.
      64             :  * It cannot handle NULL arguments, unary operators, or nondefault operators,
      65             :  * but we need none of those features for most hardwired lookups.
      66             :  *
      67             :  * We set collation to DEFAULT_COLLATION_OID always.  This is appropriate
      68             :  * for textual columns in system catalogs, and it will be ignored for
      69             :  * non-textual columns, so it's not worth trying to be more finicky.
      70             :  *
      71             :  * Note: CurrentMemoryContext at call should be as long-lived as the ScanKey
      72             :  * itself, because that's what will be used for any subsidiary info attached
      73             :  * to the ScanKey's FmgrInfo record.
      74             :  */
      75             : void
      76      408848 : ScanKeyInit(ScanKey entry,
      77             :             AttrNumber attributeNumber,
      78             :             StrategyNumber strategy,
      79             :             RegProcedure procedure,
      80             :             Datum argument)
      81             : {
      82      408848 :     entry->sk_flags = 0;
      83      408848 :     entry->sk_attno = attributeNumber;
      84      408848 :     entry->sk_strategy = strategy;
      85      408848 :     entry->sk_subtype = InvalidOid;
      86      408848 :     entry->sk_collation = DEFAULT_COLLATION_OID;
      87      408848 :     entry->sk_argument = argument;
      88      408848 :     fmgr_info(procedure, &entry->sk_func);
      89      408848 : }
      90             : 
      91             : /*
      92             :  * ScanKeyEntryInitializeWithInfo
      93             :  *      Initializes a scan key entry using an already-completed FmgrInfo
      94             :  *      function lookup record.
      95             :  *
      96             :  * Note: CurrentMemoryContext at call should be as long-lived as the ScanKey
      97             :  * itself, because that's what will be used for any subsidiary info attached
      98             :  * to the ScanKey's FmgrInfo record.
      99             :  */
     100             : void
     101     1099575 : ScanKeyEntryInitializeWithInfo(ScanKey entry,
     102             :                                int flags,
     103             :                                AttrNumber attributeNumber,
     104             :                                StrategyNumber strategy,
     105             :                                Oid subtype,
     106             :                                Oid collation,
     107             :                                FmgrInfo *finfo,
     108             :                                Datum argument)
     109             : {
     110     1099575 :     entry->sk_flags = flags;
     111     1099575 :     entry->sk_attno = attributeNumber;
     112     1099575 :     entry->sk_strategy = strategy;
     113     1099575 :     entry->sk_subtype = subtype;
     114     1099575 :     entry->sk_collation = collation;
     115     1099575 :     entry->sk_argument = argument;
     116     1099575 :     fmgr_info_copy(&entry->sk_func, finfo, CurrentMemoryContext);
     117     1099575 : }