diff options
Diffstat (limited to 'src/include/access/tupdesc.h')
| -rw-r--r-- | src/include/access/tupdesc.h | 97 |
1 files changed, 3 insertions, 94 deletions
diff --git a/src/include/access/tupdesc.h b/src/include/access/tupdesc.h index bca2ae8afb3..8930a28d660 100644 --- a/src/include/access/tupdesc.h +++ b/src/include/access/tupdesc.h @@ -46,39 +46,6 @@ typedef struct TupleConstr } TupleConstr; /* - * CompactAttribute - * Cut-down version of FormData_pg_attribute for faster access for tasks - * such as tuple deformation. These values are populated using the - * populate_compact_attribute function, which must be called directly - * after the FormData_pg_attribute struct is populated or altered in any - * way. - * - * Currently, this struct is 16 bytes. Any code changes which enlarge this - * struct should be considered very carefully. - * - * Code which must access a TupleDesc's attribute data should always make use - * of the CompactAttribute when the required fields are available there. It's - * more efficient to access the memory in CompactAttribute due to it both - * being a more compact representation of FormData_pg_attribute, but also - * because accessing the FormData_pg_attribute requires an additional pointer - * indirection through TupleDescData.attrs - */ -typedef struct CompactAttribute -{ - int32 attcacheoff; /* fixed offset into tuple, if known, or -1 */ - int16 attlen; /* attr len in bytes or -1 = varlen, -2 = - * cstring */ - bool attbyval; /* as FormData_pg_attribute.attbyval */ - bool attispackable; /* FormData_pg_attribute.attstorage != - * TYPSTORAGE_PLAIN */ - bool atthasmissing; /* as FormData_pg_attribute.atthasmissing */ - bool attisdropped; /* as FormData_pg_attribute.attisdropped */ - bool attgenerated; /* FormData_pg_attribute.attgenerated != '\0' */ - bool attnotnull; /* as FormData_pg_attribute.attnotnull */ - char attalign; /* alignment requirement */ -} CompactAttribute; - -/* * This struct is passed around within the backend to describe the structure * of tuples. For tuples coming from on-disk relations, the information is * collected from the pg_attribute, pg_attrdef, and pg_constraint catalogs. @@ -108,18 +75,6 @@ typedef struct CompactAttribute * context and go away when the context is freed. We set the tdrefcount * field of such a descriptor to -1, while reference-counted descriptors * always have tdrefcount >= 0. - * - * The attrs field stores the fixed-sized portion of FormData_pg_attribute. - * Because that struct is large, we also store a corresponding - * CompactAttribute for each attribute in compact_attrs. compact_attrs is - * stored inline with the struct. Because CompactAttribute is significantly - * smaller than FormData_pg_attribute, code, especially performance-critical - * code, should prioritize using the fields from the CompactAttribute over the - * equivalent fields in FormData_pg_attribute whenever possible. - * - * Any code making changes manually to the fields in 'attrs' must subsequently - * call populate_compact_attribute() to flush the changes out to the - * corresponding 'compact_attrs' element. */ typedef struct TupleDescData { @@ -129,53 +84,13 @@ typedef struct TupleDescData int tdrefcount; /* reference count, or -1 if not counting */ TupleConstr *constr; /* constraints, or NULL if none */ /* attrs[N] is the description of Attribute Number N+1 */ - FormData_pg_attribute *attrs; - CompactAttribute compact_attrs[FLEXIBLE_ARRAY_MEMBER]; + FormData_pg_attribute attrs[FLEXIBLE_ARRAY_MEMBER]; } TupleDescData; typedef struct TupleDescData *TupleDesc; -extern void populate_compact_attribute(TupleDesc tupdesc, int attnum); - -/* Accessor for the i'th FormData_pg_attribute of tupdesc. */ +/* Accessor for the i'th attribute of tupdesc. */ #define TupleDescAttr(tupdesc, i) (&(tupdesc)->attrs[(i)]) -/* - * Accessor for the i'th CompactAttribute of tupdesc. - */ -static inline CompactAttribute * -TupleDescCompactAttr(TupleDesc tupdesc, int i) -{ - CompactAttribute *cattr = &tupdesc->compact_attrs[i]; -#ifdef USE_ASSERT_CHECKING - CompactAttribute snapshot; - - /* - * In Assert enabled builds we verify that the CompactAttribute is - * populated correctly. This helps find bugs in places such as ALTER - * TABLE where code makes changes to the FormData_pg_attribute but forgets - * to call populate_compact_attribute. - */ - - /* - * Take a snapshot of how the CompactAttribute is now before calling - * populate_compact_attribute to make it up-to-date with the - * FormData_pg_attribute. - */ - memcpy(&snapshot, cattr, sizeof(CompactAttribute)); - - populate_compact_attribute(tupdesc, i); - - /* reset attcacheoff back to what it was */ - cattr->attcacheoff = snapshot.attcacheoff; - - /* Ensure the snapshot matches the freshly populated CompactAttribute */ - Assert(memcmp(&snapshot, cattr, sizeof(CompactAttribute)) == 0); -#endif - - return cattr; -} - - extern TupleDesc CreateTemplateTupleDesc(int natts); extern TupleDesc CreateTupleDesc(int natts, Form_pg_attribute *attrs); @@ -185,15 +100,9 @@ extern TupleDesc CreateTupleDescCopy(TupleDesc tupdesc); extern TupleDesc CreateTupleDescCopyConstr(TupleDesc tupdesc); #define TupleDescSize(src) \ - (offsetof(struct TupleDescData, compact_attrs) + \ - (src)->natts * sizeof(CompactAttribute) + \ + (offsetof(struct TupleDescData, attrs) + \ (src)->natts * sizeof(FormData_pg_attribute)) -#define TupleDescAttrAddress(desc) \ - (Form_pg_attribute) ((char *) (desc) + \ - (offsetof(struct TupleDescData, compact_attrs) + \ - (desc)->natts * sizeof(CompactAttribute))) - extern void TupleDescCopy(TupleDesc dst, TupleDesc src); extern void TupleDescCopyEntry(TupleDesc dst, AttrNumber dstAttno, |