diff options
Diffstat (limited to 'src/include/nodes/relation.h')
| -rw-r--r-- | src/include/nodes/relation.h | 106 |
1 files changed, 63 insertions, 43 deletions
diff --git a/src/include/nodes/relation.h b/src/include/nodes/relation.h index 0f143017b2..55850cef5e 100644 --- a/src/include/nodes/relation.h +++ b/src/include/nodes/relation.h @@ -6,7 +6,7 @@ * * Copyright (c) 1994, Regents of the University of California * - * $Id: relation.h,v 1.39 1999/11/23 20:07:02 momjian Exp $ + * $Id: relation.h,v 1.40 2000/01/09 00:26:44 tgl Exp $ * *------------------------------------------------------------------------- */ @@ -33,13 +33,10 @@ typedef List *Relids; * * relids - List of base-relation identifiers; it is a base relation * if there is just one, a join relation if more than one - * indexed - true if the relation has secondary indices - * pages - number of pages in the relation - * tuples - number of tuples in the relation - * size - estimated number of tuples in the relation after restriction - * clauses have been applied + * rows - estimated number of tuples in the relation after restriction + * clauses have been applied (ie, output rows of a plan for it) * width - avg. number of bytes per tuple in the relation after the - * appropriate projections have been done + * appropriate projections have been done (ie, output width) * targetlist - List of TargetList nodes * pathlist - List of Path nodes, one for each potentially useful * method of generating the relation @@ -47,20 +44,11 @@ typedef List *Relids; * pruneable - flag to let the planner know whether it can prune the * pathlist of this RelOptInfo or not. * - * * If the relation is a (secondary) index it will have the following - * fields set: - * - * classlist - List of PG_AMOPCLASS OIDs for the index - * indexkeys - List of base-relation attribute numbers that are index keys - * ordering - List of PG_OPERATOR OIDs which order the indexscan result - * relam - the OID of the pg_am of the index - * - * NB. the last element of the arrays classlist, indexkeys and ordering - * is always 0. + * * If the relation is a base relation it will have these fields set: * - * Index relations do not participate in the join tree in the way - * that regular base relations do, but it is still convenient to - * represent them by RelOptInfos. + * indexed - true if the relation has secondary indices + * pages - number of disk pages in relation + * tuples - number of tuples in relation (not considering restrictions) * * * The presence of the remaining fields depends on the restrictions * and joins that the relation participates in: @@ -79,16 +67,11 @@ typedef struct RelOptInfo NodeTag type; /* all relations included in this RelOptInfo */ - Relids relids; /* integer list of base relids */ - - /* catalog statistics information */ - bool indexed; - int pages; - int tuples; + Relids relids; /* integer list of base relids (RT indexes) */ - /* estimates generated by planner. XXX int is probably too small... */ - int size; - int width; + /* size estimates generated by planner */ + double rows; /* estimated number of result tuples */ + int width; /* estimated avg width of result tuples */ /* materialization information */ List *targetlist; @@ -96,14 +79,10 @@ typedef struct RelOptInfo struct Path *cheapestpath; bool pruneable; - /* used solely by indices: */ - Oid *classlist; /* classes of AM operators */ - int *indexkeys; /* keys over which we're indexing */ - Oid *ordering; /* OIDs of sort operators for each key */ - Oid relam; /* OID of the access method (in pg_am) */ - - Oid indproc; /* if a functional index */ - List *indpred; /* if a partial index */ + /* statistics from pg_class (only valid if it's a base rel!) */ + bool indexed; + long pages; + double tuples; /* used by various scans and joins: */ List *restrictinfo; /* RestrictInfo structures */ @@ -116,6 +95,48 @@ typedef struct RelOptInfo } RelOptInfo; /* + * IndexOptInfo + * Per-index information for planning/optimization + * + * Prior to Postgres 7.0, RelOptInfo was used to describe both relations + * and indexes, but that created confusion without actually doing anything + * useful. So now we have a separate IndexOptInfo struct for indexes. + * + * indexoid - OID of the index relation itself + * pages - number of disk pages in index + * tuples - number of index tuples in index + * classlist - List of PG_AMOPCLASS OIDs for the index + * indexkeys - List of base-relation attribute numbers that are index keys + * ordering - List of PG_OPERATOR OIDs which order the indexscan result + * relam - the OID of the pg_am of the index + * indproc - OID of the function if a functional index, else 0 + * indpred - index predicate if a partial index, else NULL + * + * NB. the last element of the arrays classlist, indexkeys and ordering + * is always 0. + */ + +typedef struct IndexOptInfo +{ + NodeTag type; + + Oid indexoid; /* OID of the index relation */ + + /* statistics from pg_class */ + long pages; + double tuples; + + /* index descriptor information */ + Oid *classlist; /* classes of AM operators */ + int *indexkeys; /* keys over which we're indexing */ + Oid *ordering; /* OIDs of sort operators for each key */ + Oid relam; /* OID of the access method (in pg_am) */ + + Oid indproc; /* if a functional index */ + List *indpred; /* if a partial index */ +} IndexOptInfo; + +/* * PathKeys * * The sort ordering of a path is represented by a list of sublists of @@ -208,8 +229,6 @@ typedef struct JoinPath { Path path; - List *pathinfo; /* copy of parent->restrictinfo; REMOVE? */ - Path *outerjoinpath; /* path for the outer side of the join */ Path *innerjoinpath; /* path for the inner side of the join */ } JoinPath; @@ -296,10 +315,10 @@ typedef struct RestrictInfo NodeTag type; Expr *clause; /* the represented clause of WHERE cond */ - Cost selectivity; /* estimated selectivity */ /* only used if clause is an OR clause: */ - List *subclauseindices; /* lists of indexes matching subclauses */ + List *subclauseindices; /* indexes matching subclauses */ + /* subclauseindices is a List of Lists of IndexOptInfos */ /* valid if clause is mergejoinable, else InvalidOid: */ Oid mergejoinoperator; /* copy of clause operator */ @@ -346,7 +365,8 @@ typedef struct JoinInfo * cinfo -- if NULL, this stream node referes to the path node. * Otherwise this is a pointer to the current clause. * clausetype -- whether cinfo is in loc_restrictinfo or pathinfo in the - * path node (XXX this is now used only by dead code...) + * path node (XXX this is now used only by dead code, which is + * good because the distinction no longer exists...) * upstream -- linked list pointer upwards * downstream -- ditto, downwards * groupup -- whether or not this node is in a group with the node upstream @@ -365,7 +385,7 @@ typedef struct Stream StreamPtr downstream; bool groupup; Cost groupcost; - Cost groupsel; + Selectivity groupsel; } Stream; #endif /* RELATION_H */ |