Hi,
When reading the code for Gin Index, there are lots of confusion about
some concepts, so here are some questions in my mind.
1. search mode.
/*
* searchMode settings for extractQueryFn.
*/
#define GIN_SEARCH_MODE_DEFAULT 0
#define GIN_SEARCH_MODE_INCLUDE_EMPTY 1
#define GIN_SEARCH_MODE_ALL 2
#define GIN_SEARCH_MODE_EVERYTHING 3 /* for internal use only */
2.
typedef struct GinScanEntryData
{
..
bool isPartialMatch;
..
}
3. requiredEntries / additionalEntries
typedef struct GinScanKeyData
{
/*
* At least one of the entries in requiredEntries must be present for a
* tuple to match the overall qual.
*
* additionalEntries contains entries that are needed by the consistent
* function to decide if an item matches, but are not sufficient to
* satisfy the qual without entries from requiredEntries.
*/
GinScanEntry *requiredEntries;
int nrequired;
GinScanEntry *additionalEntries;
int nadditional;
..
}
For all the 3 questions, the general question is what is X and how does
it play its role? I have read the gin/README before asking, so any help
is appreciated.
--
Best Regards
Andy Fan
