diff options
Diffstat (limited to 'src/include/access/gist.h')
| -rw-r--r-- | src/include/access/gist.h | 45 |
1 files changed, 40 insertions, 5 deletions
diff --git a/src/include/access/gist.h b/src/include/access/gist.h index 6902f4115b7..8292956cc09 100644 --- a/src/include/access/gist.h +++ b/src/include/access/gist.h @@ -16,6 +16,7 @@ #ifndef GIST_H #define GIST_H +#include "access/transam.h" #include "access/xlog.h" #include "access/xlogdefs.h" #include "storage/block.h" @@ -140,8 +141,6 @@ typedef struct GISTENTRY #define GIST_LEAF(entry) (GistPageIsLeaf((entry)->page)) #define GistPageIsDeleted(page) ( GistPageGetOpaque(page)->flags & F_DELETED) -#define GistPageSetDeleted(page) ( GistPageGetOpaque(page)->flags |= F_DELETED) -#define GistPageSetNonDeleted(page) ( GistPageGetOpaque(page)->flags &= ~F_DELETED) #define GistTuplesDeleted(page) ( GistPageGetOpaque(page)->flags & F_TUPLES_DELETED) #define GistMarkTuplesDeleted(page) ( GistPageGetOpaque(page)->flags |= F_TUPLES_DELETED) @@ -158,9 +157,45 @@ typedef struct GISTENTRY #define GistPageGetNSN(page) ( PageXLogRecPtrGet(GistPageGetOpaque(page)->nsn)) #define GistPageSetNSN(page, val) ( PageXLogRecPtrSet(GistPageGetOpaque(page)->nsn, val)) -/* For deleted pages we store last xid which could see the page in scan */ -#define GistPageGetDeleteXid(page) ( ((PageHeader) (page))->pd_prune_xid ) -#define GistPageSetDeleteXid(page, val) ( ((PageHeader) (page))->pd_prune_xid = val) + +/* + * On a deleted page, we store this struct. A deleted page doesn't contain any + * tuples, so we don't use the normal page layout with line pointers. Instead, + * this struct is stored right after the standard page header. pd_lower points + * to the end of this struct. If we add fields to this struct in the future, we + * can distinguish the old and new formats by pd_lower. + */ +typedef struct GISTDeletedPageContents +{ + /* last xid which could see the page in a scan */ + FullTransactionId deleteXid; +} GISTDeletedPageContents; + +static inline void +GistPageSetDeleted(Page page, FullTransactionId deletexid) +{ + Assert(PageIsEmpty(page)); + + GistPageGetOpaque(page)->flags |= F_DELETED; + ((PageHeader) page)->pd_lower = MAXALIGN(SizeOfPageHeaderData) + sizeof(GISTDeletedPageContents); + + ((GISTDeletedPageContents *) PageGetContents(page))->deleteXid = deletexid; +} + +static inline FullTransactionId +GistPageGetDeleteXid(Page page) +{ + Assert(GistPageIsDeleted(page)); + + /* Is the deleteXid field present? */ + if (((PageHeader) page)->pd_lower >= MAXALIGN(SizeOfPageHeaderData) + + offsetof(GISTDeletedPageContents, deleteXid) + sizeof(FullTransactionId)) + { + return ((GISTDeletedPageContents *) PageGetContents(page))->deleteXid; + } + else + return FullTransactionIdFromEpochAndXid(0, FirstNormalTransactionId); +} /* * Vector of GISTENTRY structs; user-defined methods union and picksplit |