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- /*
- * rtree.h -- common declarations for the rtree access method code.
- *
- * $Header: /private/postgres/src/lib/H/access/RCS/rtree.h,v 1.4 1991/05/22 07:48:42 mao Exp $
- */
-
- #ifndef RTreeHIncluded
- #define RTreeHIncluded
-
- /* see rtstrat.c for what all this is about */
- #define RTNStrategies 8
- #define RTLeftStrategyNumber 1
- #define RTOverLeftStrategyNumber 2
- #define RTOverlapStrategyNumber 3
- #define RTOverRightStrategyNumber 4
- #define RTRightStrategyNumber 5
- #define RTSameStrategyNumber 6
- #define RTContainsStrategyNumber 7
- #define RTContainedByStrategyNumber 8
-
- #define RTNProcs 3
- #define RT_UNION_PROC 1
- #define RT_INTER_PROC 2
- #define RT_SIZE_PROC 3
-
- #define F_LEAF (1 << 0)
-
- typedef struct RTreePageOpaqueData {
- uint32 flags;
- } RTreePageOpaqueData;
-
- typedef RTreePageOpaqueData *RTreePageOpaque;
-
- /*
- * When we descend a tree, we keep a stack of parent pointers.
- */
-
- typedef struct RTSTACK {
- struct RTSTACK *rts_parent;
- OffsetIndex rts_child;
- BlockNumber rts_blk;
- } RTSTACK;
-
- /*
- * When we're doing a scan, we need to keep track of the parent stack
- * for the marked and current items. Also, rtrees have the following
- * property: if you're looking for the box (1,1,2,2), on the internal
- * nodes you have to search for all boxes that *contain* (1,1,2,2), and
- * not the ones that match it. We have a private scan key for internal
- * nodes in the opaque structure for rtrees for this reason. See
- * access/index-rtree/rtscan.c and rtstrat.c for how it gets initialized.
- */
-
- typedef struct RTreeScanOpaqueData {
- struct RTSTACK *s_stack;
- struct RTSTACK *s_markstk;
- uint16 s_flags;
- uint16 s_internalNKey;
- ScanKeyData s_internalKey;
- } RTreeScanOpaqueData;
-
- typedef RTreeScanOpaqueData *RTreeScanOpaque;
-
- /*
- * When we're doing a scan and updating a tree at the same time, the
- * updates may affect the scan. We use the flags entry of the scan's
- * opaque space to record our actual position in response to updates
- * that we can't handle simply by adjusting pointers.
- */
-
- #define RTS_CURBEFORE ((uint16) (1 << 0))
- #define RTS_MRKBEFORE ((uint16) (1 << 1))
-
- /* root page of an rtree */
- #define P_ROOT 0
-
- /*
- * When we update a relation on which we're doing a scan, we need to
- * check the scan and fix it if the update affected any of the pages it
- * touches. Otherwise, we can miss records that we should see. The only
- * times we need to do this are for deletions and splits. See the code in
- * rtscan.c for how the scan is fixed. These two contants tell us what sort
- * of operation changed the index.
- */
-
- #define RTOP_DEL 0
- #define RTOP_SPLIT 1
-
- #endif /* RTreeHIncluded */
-