diff options
Diffstat (limited to 'src/include/access/skey.h')
| -rw-r--r-- | src/include/access/skey.h | 23 |
1 files changed, 17 insertions, 6 deletions
diff --git a/src/include/access/skey.h b/src/include/access/skey.h index a82e46ee0e1..b9c61cd10ae 100644 --- a/src/include/access/skey.h +++ b/src/include/access/skey.h @@ -55,18 +55,27 @@ typedef uint16 StrategyNumber; * If the operator is collation-sensitive, sk_collation must be set * correctly as well. * + * A ScanKey can also represent a ScalarArrayOpExpr, that is a condition + * "column op ANY(ARRAY[...])". This is signaled by the SK_SEARCHARRAY + * flag bit. The sk_argument is not a value of the operator's right-hand + * argument type, but rather an array of such values, and the per-element + * comparisons are to be ORed together. + * * A ScanKey can also represent a condition "column IS NULL" or "column * IS NOT NULL"; these cases are signaled by the SK_SEARCHNULL and * SK_SEARCHNOTNULL flag bits respectively. The argument is always NULL, * and the sk_strategy, sk_subtype, sk_collation, and sk_func fields are - * not used (unless set by the index AM). Currently, SK_SEARCHNULL and - * SK_SEARCHNOTNULL are supported only for index scans, not heap scans; - * and not all index AMs support them. + * not used (unless set by the index AM). + * + * SK_SEARCHARRAY, SK_SEARCHNULL and SK_SEARCHNOTNULL are supported only + * for index scans, not heap scans; and not all index AMs support them, + * only those that set amsearcharray or amsearchnulls respectively. * * A ScanKey can also represent an ordering operator invocation, that is * an ordering requirement "ORDER BY indexedcol op constant". This looks * the same as a comparison operator, except that the operator doesn't * (usually) yield boolean. We mark such ScanKeys with SK_ORDER_BY. + * SK_SEARCHARRAY, SK_SEARCHNULL, SK_SEARCHNOTNULL cannot be used here. * * Note: in some places, ScanKeys are used as a convenient representation * for the invocation of an access method support procedure. In this case @@ -114,6 +123,7 @@ typedef ScanKeyData *ScanKey; * opclass, NOT the operator's implementation function. * sk_strategy must be the same in all elements of the subsidiary array, * that is, the same as in the header entry. + * SK_SEARCHARRAY, SK_SEARCHNULL, SK_SEARCHNOTNULL cannot be used here. */ /* @@ -128,10 +138,11 @@ typedef ScanKeyData *ScanKey; #define SK_ROW_HEADER 0x0004 /* row comparison header (see above) */ #define SK_ROW_MEMBER 0x0008 /* row comparison member (see above) */ #define SK_ROW_END 0x0010 /* last row comparison member */ -#define SK_SEARCHNULL 0x0020 /* scankey represents "col IS NULL" */ -#define SK_SEARCHNOTNULL 0x0040 /* scankey represents "col IS NOT +#define SK_SEARCHARRAY 0x0020 /* scankey represents ScalarArrayOp */ +#define SK_SEARCHNULL 0x0040 /* scankey represents "col IS NULL" */ +#define SK_SEARCHNOTNULL 0x0080 /* scankey represents "col IS NOT * NULL" */ -#define SK_ORDER_BY 0x0080 /* scankey is for ORDER BY op */ +#define SK_ORDER_BY 0x0100 /* scankey is for ORDER BY op */ /* |