korsygfhrtzangaiide

/*------------------------------------------------------------------------- * * htup.h * POSTGRES heap tuple definitions. * * * Portions Copyright (c) 1996-2012, PostgreSQL Global Development Group * Portions Copyright (c) 1994, Regents of the University of California * * src/include/access/htup.h * *------------------------------------------------------------------------- */ #ifndef HTUP_H #define HTUP_H #include "access/tupdesc.h" #include "access/tupmacs.h" #include "storage/bufpage.h" #include "storage/itemptr.h" #include "storage/relfilenode.h" /* * MaxTupleAttributeNumber limits the number of (user) columns in a tuple. * The key limit on this value is that the size of the fixed overhead for * a tuple, plus the size of the null-values bitmap (at 1 bit per column), * plus MAXALIGN alignment, must fit into t_hoff which is uint8. On most * machines the upper limit without making t_hoff wider would be a little * over 1700. We use round numbers here and for MaxHeapAttributeNumber * so that alterations in HeapTupleHeaderData layout won't change the * supported max number of columns. */ #define MaxTupleAttributeNumber 1664 /* 8 * 208 */ /* * MaxHeapAttributeNumber limits the number of (user) columns in a table. * This should be somewhat less than MaxTupleAttributeNumber. It must be * at least one less, else we will fail to do UPDATEs on a maximal-width * table (because UPDATE has to form working tuples that include CTID). * In practice we want some additional daylight so that we can gracefully * support operations that add hidden "resjunk" columns, for example * SELECT * FROM wide_table ORDER BY foo, bar, baz. * In any case, depending on column data types you will likely be running * into the disk-block-based limit on overall tuple size if you have more * than a thousand or so columns. TOAST won't help. */ #define MaxHeapAttributeNumber 1600 /* 8 * 200 */ /* * Heap tuple header. To avoid wasting space, the fields should be * laid out in such a way as to avoid structure padding. * * Datums of composite types (row types) share the same general structure * as on-disk tuples, so that the same routines can be used to build and * examine them. However the requirements are slightly different: a Datum * does not need any transaction visibility information, and it does need * a length word and some embedded type information. We can achieve this * by overlaying the xmin/cmin/xmax/cmax/xvac fields of a heap tuple * with the fields needed in the Datum case. Typically, all tuples built * in-memory will be initialized with the Datum fields; but when a tuple is * about to be inserted in a table, the transaction fields will be filled, * overwriting the datum fields. * * The overall structure of a heap tuple looks like: * fixed fields (HeapTupleHeaderData struct) * nulls bitmap (if HEAP_HASNULL is set in t_infomask) * alignment padding (as needed to make user data MAXALIGN'd) * object ID (if HEAP_HASOID is set in t_infomask) * user data fields * * We store five "virtual" fields Xmin, Cmin, Xmax, Cmax, and Xvac in three * physical fields. Xmin and Xmax are always really stored, but Cmin, Cmax * and Xvac share a field. This works because we know that Cmin and Cmax * are only interesting for the lifetime of the inserting and deleting * transaction respectively. If a tuple is inserted and deleted in the same * transaction, we store a "combo" command id that can be mapped to the real * cmin and cmax, but only by use of local state within the originating * backend. See combocid.c for more details. Meanwhile, Xvac is only set by * old-style VACUUM FULL, which does not have any command sub-structure and so * does not need either Cmin or Cmax. (This requires that old-style VACUUM * FULL never try to move a tuple whose Cmin or Cmax is still interesting, * ie, an insert-in-progress or delete-in-progress tuple.) * * A word about t_ctid: whenever a new tuple is stored on disk, its t_ctid * is initialized with its own TID (location). If the tuple is ever updated, * its t_ctid is changed to point to the replacement version of the tuple. * Thus, a tuple is the latest version of its row iff XMAX is invalid or * t_ctid points to itself (in which case, if XMAX is valid, the tuple is * either locked or deleted). One can follow the chain of t_ctid links * to find the newest version of the row. Beware however that VACUUM might * erase the pointed-to (newer) tuple before erasing the pointing (older) * tuple. Hence, when following a t_ctid link, it is necessary to check * to see if the referenced slot is empty or contains an unrelated tuple. * Check that the referenced tuple has XMIN equal to the referencing tuple's * XMAX to verify that it is actually the descendant version and not an * unrelated tuple stored into a slot recently freed by VACUUM. If either * check fails, one may assume that there is no live descendant version. * * Following the fixed header fields, the nulls bitmap is stored (beginning * at t_bits). The bitmap is *not* stored if t_infomask shows that there * are no nulls in the tuple. If an OID field is present (as indicated by * t_infomask), then it is stored just before the user data, which begins at * the offset shown by t_hoff. Note that t_hoff must be a multiple of * MAXALIGN. */ typedef struct HeapTupleFields { TransactionId t_xmin; /* inserting xact ID */ TransactionId t_xmax; /* deleting or locking xact ID */ union { CommandId t_cid; /* inserting or deleting command ID, or both */ TransactionId t_xvac; /* old-style VACUUM FULL xact ID */ } t_field3; } HeapTupleFields; typedef struct DatumTupleFields { int32 datum_len_; /* varlena header (do not touch directly!) */ int32 datum_typmod; /* -1, or identifier of a record type */ Oid datum_typeid; /* composite type OID, or RECORDOID */ /* * Note: field ordering is chosen with thought that Oid might someday * widen to 64 bits. */ } DatumTupleFields; typedef struct HeapTupleHeaderData { union { HeapTupleFields t_heap; DatumTupleFields t_datum; } t_choice; ItemPointerData t_ctid; /* current TID of this or newer tuple */ /* Fields below here must match MinimalTupleData! */ uint16 t_infomask2; /* number of attributes + various flags */ uint16 t_infomask; /* various flag bits, see below */ uint8 t_hoff; /* sizeof header incl. bitmap, padding */ /* ^ - 23 bytes - ^ */ bits8 t_bits[1]; /* bitmap of NULLs -- VARIABLE LENGTH */ /* MORE DATA FOLLOWS AT END OF STRUCT */ } HeapTupleHeaderData; typedef HeapTupleHeaderData *HeapTupleHeader; /* * information stored in t_infomask: */ #define HEAP_HASNULL 0x0001 /* has null attribute(s) */ #define HEAP_HASVARWIDTH 0x0002 /* has variable-width attribute(s) */ #define HEAP_HASEXTERNAL 0x0004 /* has external stored attribute(s) */ #define HEAP_HASOID 0x0008 /* has an object-id field */ /* bit 0x0010 is available */ #define HEAP_COMBOCID 0x0020 /* t_cid is a combo cid */ #define HEAP_XMAX_EXCL_LOCK 0x0040 /* xmax is exclusive locker */ #define HEAP_XMAX_SHARED_LOCK 0x0080 /* xmax is shared locker */ /* if either LOCK bit is set, xmax hasn't deleted the tuple, only locked it */ #define HEAP_IS_LOCKED (HEAP_XMAX_EXCL_LOCK | HEAP_XMAX_SHARED_LOCK) #define HEAP_XMIN_COMMITTED 0x0100 /* t_xmin committed */ #define HEAP_XMIN_INVALID 0x0200 /* t_xmin invalid/aborted */ #define HEAP_XMAX_COMMITTED 0x0400 /* t_xmax committed */ #define HEAP_XMAX_INVALID 0x0800 /* t_xmax invalid/aborted */ #define HEAP_XMAX_IS_MULTI 0x1000 /* t_xmax is a MultiXactId */ #define HEAP_UPDATED 0x2000 /* this is UPDATEd version of row */ #define HEAP_MOVED_OFF 0x4000 /* moved to another place by pre-9.0 * VACUUM FULL; kept for binary * upgrade support */ #define HEAP_MOVED_IN 0x8000 /* moved from another place by pre-9.0 * VACUUM FULL; kept for binary * upgrade support */ #define HEAP_MOVED (HEAP_MOVED_OFF | HEAP_MOVED_IN) #define HEAP_XACT_MASK 0xFFE0 /* visibility-related bits */ /* * information stored in t_infomask2: */ #define HEAP_NATTS_MASK 0x07FF /* 11 bits for number of attributes */ /* bits 0x3800 are available */ #define HEAP_HOT_UPDATED 0x4000 /* tuple was HOT-updated */ #define HEAP_ONLY_TUPLE 0x8000 /* this is heap-only tuple */ #define HEAP2_XACT_MASK 0xC000 /* visibility-related bits */ /* * HEAP_TUPLE_HAS_MATCH is a temporary flag used during hash joins. It is * only used in tuples that are in the hash table, and those don't need * any visibility information, so we can overlay it on a visibility flag * instead of using up a dedicated bit. */ #define HEAP_TUPLE_HAS_MATCH HEAP_ONLY_TUPLE /* tuple has a join match */ /* * HeapTupleHeader accessor macros * * Note: beware of multiple evaluations of "tup" argument. But the Set * macros evaluate their other argument only once. */ #define HeapTupleHeaderGetXmin(tup) \ ( \ (tup)->t_choice.t_heap.t_xmin \ ) #define HeapTupleHeaderSetXmin(tup, xid) \ ( \ (tup)->t_choice.t_heap.t_xmin = (xid) \ ) #define HeapTupleHeaderGetXmax(tup) \ ( \ (tup)->t_choice.t_heap.t_xmax \ ) #define HeapTupleHeaderSetXmax(tup, xid) \ ( \ (tup)->t_choice.t_heap.t_xmax = (xid) \ ) /* * HeapTupleHeaderGetRawCommandId will give you what's in the header whether * it is useful or not. Most code should use HeapTupleHeaderGetCmin or * HeapTupleHeaderGetCmax instead, but note that those Assert that you can * get a legitimate result, ie you are in the originating transaction! */ #define HeapTupleHeaderGetRawCommandId(tup) \ ( \ (tup)->t_choice.t_heap.t_field3.t_cid \ ) /* SetCmin is reasonably simple since we never need a combo CID */ #define HeapTupleHeaderSetCmin(tup, cid) \ do { \ Assert(!((tup)->t_infomask & HEAP_MOVED)); \ (tup)->t_choice.t_heap.t_field3.t_cid = (cid); \ (tup)->t_infomask &= ~HEAP_COMBOCID; \ } while (0) /* SetCmax must be used after HeapTupleHeaderAdjustCmax; see combocid.c */ #define HeapTupleHeaderSetCmax(tup, cid, iscombo) \ do { \ Assert(!((tup)->t_infomask & HEAP_MOVED)); \ (tup)->t_choice.t_heap.t_field3.t_cid = (cid); \ if (iscombo) \ (tup)->t_infomask |= HEAP_COMBOCID; \ else \ (tup)->t_infomask &= ~HEAP_COMBOCID; \ } while (0) #define HeapTupleHeaderGetXvac(tup) \ ( \ ((tup)->t_infomask & HEAP_MOVED) ? \ (tup)->t_choice.t_heap.t_field3.t_xvac \ : \ InvalidTransactionId \ ) #define HeapTupleHeaderSetXvac(tup, xid) \ do { \ Assert((tup)->t_infomask & HEAP_MOVED); \ (tup)->t_choice.t_heap.t_field3.t_xvac = (xid); \ } while (0) #define HeapTupleHeaderGetDatumLength(tup) \ VARSIZE(tup) #define HeapTupleHeaderSetDatumLength(tup, len) \ SET_VARSIZE(tup, len) #define HeapTupleHeaderGetTypeId(tup) \ ( \ (tup)->t_choice.t_datum.datum_typeid \ ) #define HeapTupleHeaderSetTypeId(tup, typeid) \ ( \ (tup)->t_choice.t_datum.datum_typeid = (typeid) \ ) #define HeapTupleHeaderGetTypMod(tup) \ ( \ (tup)->t_choice.t_datum.datum_typmod \ ) #define HeapTupleHeaderSetTypMod(tup, typmod) \ ( \ (tup)->t_choice.t_datum.datum_typmod = (typmod) \ ) #define HeapTupleHeaderGetOid(tup) \ ( \ ((tup)->t_infomask & HEAP_HASOID) ? \ *((Oid *) ((char *)(tup) + (tup)->t_hoff - sizeof(Oid))) \ : \ InvalidOid \ ) #define HeapTupleHeaderSetOid(tup, oid) \ do { \ Assert((tup)->t_infomask & HEAP_HASOID); \ *((Oid *) ((char *)(tup) + (tup)->t_hoff - sizeof(Oid))) = (oid); \ } while (0) /* * Note that we stop considering a tuple HOT-updated as soon as it is known * aborted or the would-be updating transaction is known aborted. For best * efficiency, check tuple visibility before using this macro, so that the * INVALID bits will be as up to date as possible. */ #define HeapTupleHeaderIsHotUpdated(tup) \ ( \ ((tup)->t_infomask2 & HEAP_HOT_UPDATED) != 0 && \ ((tup)->t_infomask & (HEAP_XMIN_INVALID | HEAP_XMAX_INVALID)) == 0 \ ) #define HeapTupleHeaderSetHotUpdated(tup) \ ( \ (tup)->t_infomask2 |= HEAP_HOT_UPDATED \ ) #define HeapTupleHeaderClearHotUpdated(tup) \ ( \ (tup)->t_infomask2 &= ~HEAP_HOT_UPDATED \ ) #define HeapTupleHeaderIsHeapOnly(tup) \ ( \ ((tup)->t_infomask2 & HEAP_ONLY_TUPLE) != 0 \ ) #define HeapTupleHeaderSetHeapOnly(tup) \ ( \ (tup)->t_infomask2 |= HEAP_ONLY_TUPLE \ ) #define HeapTupleHeaderClearHeapOnly(tup) \ ( \ (tup)->t_infomask2 &= ~HEAP_ONLY_TUPLE \ ) #define HeapTupleHeaderHasMatch(tup) \ ( \ ((tup)->t_infomask2 & HEAP_TUPLE_HAS_MATCH) != 0 \ ) #define HeapTupleHeaderSetMatch(tup) \ ( \ (tup)->t_infomask2 |= HEAP_TUPLE_HAS_MATCH \ ) #define HeapTupleHeaderClearMatch(tup) \ ( \ (tup)->t_infomask2 &= ~HEAP_TUPLE_HAS_MATCH \ ) #define HeapTupleHeaderGetNatts(tup) \ ((tup)->t_infomask2 & HEAP_NATTS_MASK) #define HeapTupleHeaderSetNatts(tup, natts) \ ( \ (tup)->t_infomask2 = ((tup)->t_infomask2 & ~HEAP_NATTS_MASK) | (natts) \ ) #define HeapTupleHeaderHasExternal(tup) \ (((tup)->t_infomask & HEAP_HASEXTERNAL) != 0) /* * BITMAPLEN(NATTS) - * Computes size of null bitmap given number of data columns. */ #define BITMAPLEN(NATTS) (((int)(NATTS) + 7) / 8) /* * MaxHeapTupleSize is the maximum allowed size of a heap tuple, including * header and MAXALIGN alignment padding. Basically it's BLCKSZ minus the * other stuff that has to be on a disk page. Since heap pages use no * "special space", there's no deduction for that. * * NOTE: we allow for the ItemId that must point to the tuple, ensuring that * an otherwise-empty page can indeed hold a tuple of this size. Because * ItemIds and tuples have different alignment requirements, don't assume that * you can, say, fit 2 tuples of size MaxHeapTupleSize/2 on the same page. */ #define MaxHeapTupleSize (BLCKSZ - MAXALIGN(SizeOfPageHeaderData + sizeof(ItemIdData))) /* * MaxHeapTuplesPerPage is an upper bound on the number of tuples that can * fit on one heap page. (Note that indexes could have more, because they * use a smaller tuple header.) We arrive at the divisor because each tuple * must be maxaligned, and it must have an associated item pointer. * * Note: with HOT, there could theoretically be more line pointers (not actual * tuples) than this on a heap page. However we constrain the number of line * pointers to this anyway, to avoid excessive line-pointer bloat and not * require increases in the size of work arrays. */ #define MaxHeapTuplesPerPage \ ((int) ((BLCKSZ - SizeOfPageHeaderData) / \ (MAXALIGN(offsetof(HeapTupleHeaderData, t_bits)) + sizeof(ItemIdData)))) /* * MaxAttrSize is a somewhat arbitrary upper limit on the declared size of * data fields of char(n) and similar types. It need not have anything * directly to do with the *actual* upper limit of varlena values, which * is currently 1Gb (see TOAST structures in postgres.h). I've set it * at 10Mb which seems like a reasonable number --- tgl 8/6/00. */ #define MaxAttrSize (10 * 1024 * 1024) /* * MinimalTuple is an alternative representation that is used for transient * tuples inside the executor, in places where transaction status information * is not required, the tuple rowtype is known, and shaving off a few bytes * is worthwhile because we need to store many tuples. The representation * is chosen so that tuple access routines can work with either full or * minimal tuples via a HeapTupleData pointer structure. The access routines * see no difference, except that they must not access the transaction status * or t_ctid fields because those aren't there. * * For the most part, MinimalTuples should be accessed via TupleTableSlot * routines. These routines will prevent access to the "system columns" * and thereby prevent accidental use of the nonexistent fields. * * MinimalTupleData contains a length word, some padding, and fields matching * HeapTupleHeaderData beginning with t_infomask2. The padding is chosen so * that offsetof(t_infomask2) is the same modulo MAXIMUM_ALIGNOF in both * structs. This makes data alignment rules equivalent in both cases. * * When a minimal tuple is accessed via a HeapTupleData pointer, t_data is * set to point MINIMAL_TUPLE_OFFSET bytes before the actual start of the * minimal tuple --- that is, where a full tuple matching the minimal tuple's * data would start. This trick is what makes the structs seem equivalent. * * Note that t_hoff is computed the same as in a full tuple, hence it includes * the MINIMAL_TUPLE_OFFSET distance. t_len does not include that, however. * * MINIMAL_TUPLE_DATA_OFFSET is the offset to the first useful (non-pad) data * other than the length word. tuplesort.c and tuplestore.c use this to avoid * writing the padding to disk. */ #define MINIMAL_TUPLE_OFFSET \ ((offsetof(HeapTupleHeaderData, t_infomask2) - sizeof(uint32)) / MAXIMUM_ALIGNOF * MAXIMUM_ALIGNOF) #define MINIMAL_TUPLE_PADDING \ ((offsetof(HeapTupleHeaderData, t_infomask2) - sizeof(uint32)) % MAXIMUM_ALIGNOF) #define MINIMAL_TUPLE_DATA_OFFSET \ offsetof(MinimalTupleData, t_infomask2) typedef struct MinimalTupleData { uint32 t_len; /* actual length of minimal tuple */ char mt_padding[MINIMAL_TUPLE_PADDING]; /* Fields below here must match HeapTupleHeaderData! */ uint16 t_infomask2; /* number of attributes + various flags */ uint16 t_infomask; /* various flag bits, see below */ uint8 t_hoff; /* sizeof header incl. bitmap, padding */ /* ^ - 23 bytes - ^ */ bits8 t_bits[1]; /* bitmap of NULLs -- VARIABLE LENGTH */ /* MORE DATA FOLLOWS AT END OF STRUCT */ } MinimalTupleData; typedef MinimalTupleData *MinimalTuple; /* * HeapTupleData is an in-memory data structure that points to a tuple. * * There are several ways in which this data structure is used: * * * Pointer to a tuple in a disk buffer: t_data points directly into the * buffer (which the code had better be holding a pin on, but this is not * reflected in HeapTupleData itself). * * * Pointer to nothing: t_data is NULL. This is used as a failure indication * in some functions. * * * Part of a palloc'd tuple: the HeapTupleData itself and the tuple * form a single palloc'd chunk. t_data points to the memory location * immediately following the HeapTupleData struct (at offset HEAPTUPLESIZE). * This is the output format of heap_form_tuple and related routines. * * * Separately allocated tuple: t_data points to a palloc'd chunk that * is not adjacent to the HeapTupleData. (This case is deprecated since * it's difficult to tell apart from case #1. It should be used only in * limited contexts where the code knows that case #1 will never apply.) * * * Separately allocated minimal tuple: t_data points MINIMAL_TUPLE_OFFSET * bytes before the start of a MinimalTuple. As with the previous case, * this can't be told apart from case #1 by inspection; code setting up * or destroying this representation has to know what it's doing. * * t_len should always be valid, except in the pointer-to-nothing case. * t_self and t_tableOid should be valid if the HeapTupleData points to * a disk buffer, or if it represents a copy of a tuple on disk. They * should be explicitly set invalid in manufactured tuples. */ typedef struct HeapTupleData { uint32 t_len; /* length of *t_data */ ItemPointerData t_self; /* SelfItemPointer */ Oid t_tableOid; /* table the tuple came from */ HeapTupleHeader t_data; /* -> tuple header and data */ } HeapTupleData; typedef HeapTupleData *HeapTuple; #define HEAPTUPLESIZE MAXALIGN(sizeof(HeapTupleData)) /* * GETSTRUCT - given a HeapTuple pointer, return address of the user data */ #define GETSTRUCT(TUP) ((char *) ((TUP)->t_data) + (TUP)->t_data->t_hoff) /* * Accessor macros to be used with HeapTuple pointers. */ #define HeapTupleIsValid(tuple) PointerIsValid(tuple) #define HeapTupleHasNulls(tuple) \ (((tuple)->t_data->t_infomask & HEAP_HASNULL) != 0) #define HeapTupleNoNulls(tuple) \ (!((tuple)->t_data->t_infomask & HEAP_HASNULL)) #define HeapTupleHasVarWidth(tuple) \ (((tuple)->t_data->t_infomask & HEAP_HASVARWIDTH) != 0) #define HeapTupleAllFixed(tuple) \ (!((tuple)->t_data->t_infomask & HEAP_HASVARWIDTH)) #define HeapTupleHasExternal(tuple) \ (((tuple)->t_data->t_infomask & HEAP_HASEXTERNAL) != 0) #define HeapTupleIsHotUpdated(tuple) \ HeapTupleHeaderIsHotUpdated((tuple)->t_data) #define HeapTupleSetHotUpdated(tuple) \ HeapTupleHeaderSetHotUpdated((tuple)->t_data) #define HeapTupleClearHotUpdated(tuple) \ HeapTupleHeaderClearHotUpdated((tuple)->t_data) #define HeapTupleIsHeapOnly(tuple) \ HeapTupleHeaderIsHeapOnly((tuple)->t_data) #define HeapTupleSetHeapOnly(tuple) \ HeapTupleHeaderSetHeapOnly((tuple)->t_data) #define HeapTupleClearHeapOnly(tuple) \ HeapTupleHeaderClearHeapOnly((tuple)->t_data) #define HeapTupleGetOid(tuple) \ HeapTupleHeaderGetOid((tuple)->t_data) #define HeapTupleSetOid(tuple, oid) \ HeapTupleHeaderSetOid((tuple)->t_data, (oid)) /* * WAL record definitions for heapam.c's WAL operations * * XLOG allows to store some information in high 4 bits of log * record xl_info field. We use 3 for opcode and one for init bit. */ #define XLOG_HEAP_INSERT 0x00 #define XLOG_HEAP_DELETE 0x10 #define XLOG_HEAP_UPDATE 0x20 /* 0x030 is free, was XLOG_HEAP_MOVE */ #define XLOG_HEAP_HOT_UPDATE 0x40 #define XLOG_HEAP_NEWPAGE 0x50 #define XLOG_HEAP_LOCK 0x60 #define XLOG_HEAP_INPLACE 0x70 #define XLOG_HEAP_OPMASK 0x70 /* * When we insert 1st item on new page in INSERT, UPDATE, HOT_UPDATE, * or MULTI_INSERT, we can (and we do) restore entire page in redo */ #define XLOG_HEAP_INIT_PAGE 0x80 /* * We ran out of opcodes, so heapam.c now has a second RmgrId. These opcodes * are associated with RM_HEAP2_ID, but are not logically different from * the ones above associated with RM_HEAP_ID. XLOG_HEAP_OPMASK applies to * these, too. */ #define XLOG_HEAP2_FREEZE 0x00 #define XLOG_HEAP2_CLEAN 0x10 /* 0x20 is free, was XLOG_HEAP2_CLEAN_MOVE */ #define XLOG_HEAP2_CLEANUP_INFO 0x30 #define XLOG_HEAP2_VISIBLE 0x40 #define XLOG_HEAP2_MULTI_INSERT 0x50 /* * All what we need to find changed tuple * * NB: on most machines, sizeof(xl_heaptid) will include some trailing pad * bytes for alignment. We don't want to store the pad space in the XLOG, * so use SizeOfHeapTid for space calculations. Similar comments apply for * the other xl_FOO structs. */ typedef struct xl_heaptid { RelFileNode node; ItemPointerData tid; /* changed tuple id */ } xl_heaptid; #define SizeOfHeapTid (offsetof(xl_heaptid, tid) + SizeOfIptrData) /* This is what we need to know about delete */ typedef struct xl_heap_delete { xl_heaptid target; /* deleted tuple id */ bool all_visible_cleared; /* PD_ALL_VISIBLE was cleared */ } xl_heap_delete; #define SizeOfHeapDelete (offsetof(xl_heap_delete, all_visible_cleared) + sizeof(bool)) /* * We don't store the whole fixed part (HeapTupleHeaderData) of an inserted * or updated tuple in WAL; we can save a few bytes by reconstructing the * fields that are available elsewhere in the WAL record, or perhaps just * plain needn't be reconstructed. These are the fields we must store. * NOTE: t_hoff could be recomputed, but we may as well store it because * it will come for free due to alignment considerations. */ typedef struct xl_heap_header { uint16 t_infomask2; uint16 t_infomask; uint8 t_hoff; } xl_heap_header; #define SizeOfHeapHeader (offsetof(xl_heap_header, t_hoff) + sizeof(uint8)) /* This is what we need to know about insert */ typedef struct xl_heap_insert { xl_heaptid target; /* inserted tuple id */ bool all_visible_cleared; /* PD_ALL_VISIBLE was cleared */ /* xl_heap_header & TUPLE DATA FOLLOWS AT END OF STRUCT */ } xl_heap_insert; #define SizeOfHeapInsert (offsetof(xl_heap_insert, all_visible_cleared) + sizeof(bool)) /* * This is what we need to know about a multi-insert. The record consists of * xl_heap_multi_insert header, followed by a xl_multi_insert_tuple and tuple * data for each tuple. 'offsets' array is omitted if the whole page is * reinitialized (XLOG_HEAP_INIT_PAGE) */ typedef struct xl_heap_multi_insert { RelFileNode node; BlockNumber blkno; bool all_visible_cleared; uint16 ntuples; OffsetNumber offsets[1]; /* TUPLE DATA (xl_multi_insert_tuples) FOLLOW AT END OF STRUCT */ } xl_heap_multi_insert; #define SizeOfHeapMultiInsert offsetof(xl_heap_multi_insert, offsets) typedef struct xl_multi_insert_tuple { uint16 datalen; /* size of tuple data that follows */ uint16 t_infomask2; uint16 t_infomask; uint8 t_hoff; /* TUPLE DATA FOLLOWS AT END OF STRUCT */ } xl_multi_insert_tuple; #define SizeOfMultiInsertTuple (offsetof(xl_multi_insert_tuple, t_hoff) + sizeof(uint8)) /* This is what we need to know about update|hot_update */ typedef struct xl_heap_update { xl_heaptid target; /* deleted tuple id */ ItemPointerData newtid; /* new inserted tuple id */ bool all_visible_cleared; /* PD_ALL_VISIBLE was cleared */ bool new_all_visible_cleared; /* same for the page of newtid */ /* NEW TUPLE xl_heap_header AND TUPLE DATA FOLLOWS AT END OF STRUCT */ } xl_heap_update; #define SizeOfHeapUpdate (offsetof(xl_heap_update, new_all_visible_cleared) + sizeof(bool)) /* * This is what we need to know about vacuum page cleanup/redirect * * The array of OffsetNumbers following the fixed part of the record contains: * * for each redirected item: the item offset, then the offset redirected to * * for each now-dead item: the item offset * * for each now-unused item: the item offset * The total number of OffsetNumbers is therefore 2*nredirected+ndead+nunused. * Note that nunused is not explicitly stored, but may be found by reference * to the total record length. */ typedef struct xl_heap_clean { RelFileNode node; BlockNumber block; TransactionId latestRemovedXid; uint16 nredirected; uint16 ndead; /* OFFSET NUMBERS FOLLOW */ } xl_heap_clean; #define SizeOfHeapClean (offsetof(xl_heap_clean, ndead) + sizeof(uint16)) /* * Cleanup_info is required in some cases during a lazy VACUUM. * Used for reporting the results of HeapTupleHeaderAdvanceLatestRemovedXid() * see vacuumlazy.c for full explanation */ typedef struct xl_heap_cleanup_info { RelFileNode node; TransactionId latestRemovedXid; } xl_heap_cleanup_info; #define SizeOfHeapCleanupInfo (sizeof(xl_heap_cleanup_info)) /* This is for replacing a page's contents in toto */ /* NB: this is used for indexes as well as heaps */ typedef struct xl_heap_newpage { RelFileNode node; ForkNumber forknum; BlockNumber blkno; /* location of new page */ /* entire page contents follow at end of record */ } xl_heap_newpage; #define SizeOfHeapNewpage (offsetof(xl_heap_newpage, blkno) + sizeof(BlockNumber)) /* This is what we need to know about lock */ typedef struct xl_heap_lock { xl_heaptid target; /* locked tuple id */ TransactionId locking_xid; /* might be a MultiXactId not xid */ bool xid_is_mxact; /* is it? */ bool shared_lock; /* shared or exclusive row lock? */ } xl_heap_lock; #define SizeOfHeapLock (offsetof(xl_heap_lock, shared_lock) + sizeof(bool)) /* This is what we need to know about in-place update */ typedef struct xl_heap_inplace { xl_heaptid target; /* updated tuple id */ /* TUPLE DATA FOLLOWS AT END OF STRUCT */ } xl_heap_inplace; #define SizeOfHeapInplace (offsetof(xl_heap_inplace, target) + SizeOfHeapTid) /* This is what we need to know about tuple freezing during vacuum */ typedef struct xl_heap_freeze { RelFileNode node; BlockNumber block; TransactionId cutoff_xid; /* TUPLE OFFSET NUMBERS FOLLOW AT THE END */ } xl_heap_freeze; #define SizeOfHeapFreeze (offsetof(xl_heap_freeze, cutoff_xid) + sizeof(TransactionId)) /* This is what we need to know about setting a visibility map bit */ typedef struct xl_heap_visible { RelFileNode node; BlockNumber block; TransactionId cutoff_xid; } xl_heap_visible; #define SizeOfHeapVisible (offsetof(xl_heap_visible, cutoff_xid) + sizeof(TransactionId)) extern void HeapTupleHeaderAdvanceLatestRemovedXid(HeapTupleHeader tuple, TransactionId *latestRemovedXid); /* HeapTupleHeader functions implemented in utils/time/combocid.c */ extern CommandId HeapTupleHeaderGetCmin(HeapTupleHeader tup); extern CommandId HeapTupleHeaderGetCmax(HeapTupleHeader tup); extern void HeapTupleHeaderAdjustCmax(HeapTupleHeader tup, CommandId *cmax, bool *iscombo); /* ---------------- * fastgetattr * * Fetch a user attribute's value as a Datum (might be either a * value, or a pointer into the data area of the tuple). * * This must not be used when a system attribute might be requested. * Furthermore, the passed attnum MUST be valid. Use heap_getattr() * instead, if in doubt. * * This gets called many times, so we macro the cacheable and NULL * lookups, and call nocachegetattr() for the rest. * ---------------- */ #if !defined(DISABLE_COMPLEX_MACRO) #define fastgetattr(tup, attnum, tupleDesc, isnull) \ ( \ AssertMacro((attnum) > 0), \ (*(isnull) = false), \ HeapTupleNoNulls(tup) ? \ ( \ (tupleDesc)->attrs[(attnum)-1]->attcacheoff >= 0 ? \ ( \ fetchatt((tupleDesc)->attrs[(attnum)-1], \ (char *) (tup)->t_data + (tup)->t_data->t_hoff + \ (tupleDesc)->attrs[(attnum)-1]->attcacheoff) \ ) \ : \ nocachegetattr((tup), (attnum), (tupleDesc)) \ ) \ : \ ( \ att_isnull((attnum)-1, (tup)->t_data->t_bits) ? \ ( \ (*(isnull) = true), \ (Datum)NULL \ ) \ : \ ( \ nocachegetattr((tup), (attnum), (tupleDesc)) \ ) \ ) \ ) #else /* defined(DISABLE_COMPLEX_MACRO) */ extern Datum fastgetattr(HeapTuple tup, int attnum, TupleDesc tupleDesc, bool *isnull); #endif /* defined(DISABLE_COMPLEX_MACRO) */ /* ---------------- * heap_getattr * * Extract an attribute of a heap tuple and return it as a Datum. * This works for either system or user attributes. The given attnum * is properly range-checked. * * If the field in question has a NULL value, we return a zero Datum * and set *isnull == true. Otherwise, we set *isnull == false. * * <tup> is the pointer to the heap tuple. <attnum> is the attribute * number of the column (field) caller wants. <tupleDesc> is a * pointer to the structure describing the row and all its fields. * ---------------- */ #define heap_getattr(tup, attnum, tupleDesc, isnull) \ ( \ ((attnum) > 0) ? \ ( \ ((attnum) > (int) HeapTupleHeaderGetNatts((tup)->t_data)) ? \ ( \ (*(isnull) = true), \ (Datum)NULL \ ) \ : \ fastgetattr((tup), (attnum), (tupleDesc), (isnull)) \ ) \ : \ heap_getsysattr((tup), (attnum), (tupleDesc), (isnull)) \ ) /* prototypes for functions in common/heaptuple.c */ extern Size heap_compute_data_size(TupleDesc tupleDesc, Datum *values, bool *isnull); extern void heap_fill_tuple(TupleDesc tupleDesc, Datum *values, bool *isnull, char *data, Size data_size, uint16 *infomask, bits8 *bit); extern bool heap_attisnull(HeapTuple tup, int attnum); extern Datum nocachegetattr(HeapTuple tup, int attnum, TupleDesc att); extern Datum heap_getsysattr(HeapTuple tup, int attnum, TupleDesc tupleDesc, bool *isnull); extern HeapTuple heap_copytuple(HeapTuple tuple); extern void heap_copytuple_with_tuple(HeapTuple src, HeapTuple dest); extern Datum heap_copy_tuple_as_datum(HeapTuple tuple, TupleDesc tupleDesc); extern HeapTuple heap_form_tuple(TupleDesc tupleDescriptor, Datum *values, bool *isnull); extern HeapTuple heap_modify_tuple(HeapTuple tuple, TupleDesc tupleDesc, Datum *replValues, bool *replIsnull, bool *doReplace); extern void heap_deform_tuple(HeapTuple tuple, TupleDesc tupleDesc, Datum *values, bool *isnull); /* these three are deprecated versions of the three above: */ extern HeapTuple heap_formtuple(TupleDesc tupleDescriptor, Datum *values, char *nulls); extern HeapTuple heap_modifytuple(HeapTuple tuple, TupleDesc tupleDesc, Datum *replValues, char *replNulls, char *replActions); extern void heap_deformtuple(HeapTuple tuple, TupleDesc tupleDesc, Datum *values, char *nulls); extern void heap_freetuple(HeapTuple htup); extern MinimalTuple heap_form_minimal_tuple(TupleDesc tupleDescriptor, Datum *values, bool *isnull); extern void heap_free_minimal_tuple(MinimalTuple mtup); extern MinimalTuple heap_copy_minimal_tuple(MinimalTuple mtup); extern HeapTuple heap_tuple_from_minimal_tuple(MinimalTuple mtup); extern MinimalTuple minimal_tuple_from_heap_tuple(HeapTuple htup); #endif /* HTUP_H */