diff options
Diffstat (limited to 'src/include/executor/hashjoin.h')
| -rw-r--r-- | src/include/executor/hashjoin.h | 64 |
1 files changed, 35 insertions, 29 deletions
diff --git a/src/include/executor/hashjoin.h b/src/include/executor/hashjoin.h index 751b5efee1..493210ba01 100644 --- a/src/include/executor/hashjoin.h +++ b/src/include/executor/hashjoin.h @@ -6,7 +6,7 @@ * * Copyright (c) 1994, Regents of the University of California * - * $Id: hashjoin.h,v 1.11 1999/05/18 21:33:04 tgl Exp $ + * $Id: hashjoin.h,v 1.12 1999/05/25 16:13:54 momjian Exp $ * *------------------------------------------------------------------------- */ @@ -21,7 +21,7 @@ * hash-join hash table structures * * Each active hashjoin has a HashJoinTable control block which is - * palloc'd in the executor's context. All other storage needed for + * palloc'd in the executor's context. All other storage needed for * the hashjoin is kept in a private "named portal", one for each hashjoin. * This makes it easy and fast to release the storage when we don't need it * anymore. @@ -41,9 +41,10 @@ typedef struct HashJoinTupleData { - struct HashJoinTupleData *next; /* link to next tuple in same bucket */ - HeapTupleData htup; /* tuple header */ -} HashJoinTupleData; + struct HashJoinTupleData *next; /* link to next tuple in same + * bucket */ + HeapTupleData htup; /* tuple header */ +} HashJoinTupleData; typedef HashJoinTupleData *HashJoinTuple; @@ -51,40 +52,45 @@ typedef struct HashTableData { int nbuckets; /* buckets in use during this batch */ int totalbuckets; /* total number of (virtual) buckets */ - HashJoinTuple *buckets; /* buckets[i] is head of list of tuples */ + HashJoinTuple *buckets; /* buckets[i] is head of list of tuples */ /* buckets array is per-batch storage, as are all the tuples */ int nbatch; /* number of batches; 0 means 1-pass join */ int curbatch; /* current batch #, or 0 during 1st pass */ - /* all these arrays are allocated for the life of the hash join, - * but only if nbatch > 0: + /* + * all these arrays are allocated for the life of the hash join, but + * only if nbatch > 0: */ - BufFile **innerBatchFile; /* buffered virtual temp file per batch */ - BufFile **outerBatchFile; /* buffered virtual temp file per batch */ - long *outerBatchSize; /* count of tuples in each outer batch file */ - long *innerBatchSize; /* count of tuples in each inner batch file */ + BufFile **innerBatchFile; /* buffered virtual temp file per batch */ + BufFile **outerBatchFile; /* buffered virtual temp file per batch */ + long *outerBatchSize; /* count of tuples in each outer batch + * file */ + long *innerBatchSize; /* count of tuples in each inner batch + * file */ - /* During 1st scan of inner relation, we get tuples from executor. - * If nbatch > 0 then tuples that don't belong in first nbuckets logical - * buckets get dumped into inner-batch temp files. - * The same statements apply for the 1st scan of the outer relation, - * except we write tuples to outer-batch temp files. - * If nbatch > 0 then we do the following for each batch: - * 1. Read tuples from inner batch file, load into hash buckets. - * 2. Read tuples from outer batch file, match to hash buckets and output. + /* + * During 1st scan of inner relation, we get tuples from executor. If + * nbatch > 0 then tuples that don't belong in first nbuckets logical + * buckets get dumped into inner-batch temp files. The same statements + * apply for the 1st scan of the outer relation, except we write + * tuples to outer-batch temp files. If nbatch > 0 then we do the + * following for each batch: 1. Read tuples from inner batch file, + * load into hash buckets. 2. Read tuples from outer batch file, match + * to hash buckets and output. */ - /* Ugly kluge: myPortal ought to be declared as type Portal (ie, PortalD*) - * but if we try to include utils/portal.h here, we end up with a - * circular dependency of include files! Until the various node.h files - * are restructured in a cleaner way, we have to fake it. The most - * reliable fake seems to be to declare myPortal as void * and then - * cast it to the right things in nodeHash.c. + /* + * Ugly kluge: myPortal ought to be declared as type Portal (ie, + * PortalD*) but if we try to include utils/portal.h here, we end up + * with a circular dependency of include files! Until the various + * node.h files are restructured in a cleaner way, we have to fake it. + * The most reliable fake seems to be to declare myPortal as void * + * and then cast it to the right things in nodeHash.c. */ - void *myPortal; /* where to keep working storage */ - MemoryContext hashCxt; /* context for whole-hash-join storage */ - MemoryContext batchCxt; /* context for this-batch-only storage */ + void *myPortal; /* where to keep working storage */ + MemoryContext hashCxt; /* context for whole-hash-join storage */ + MemoryContext batchCxt; /* context for this-batch-only storage */ } HashTableData; typedef HashTableData *HashJoinTable; |