diff options
Diffstat (limited to 'src/include/nodes/relation.h')
| -rw-r--r-- | src/include/nodes/relation.h | 58 |
1 files changed, 29 insertions, 29 deletions
diff --git a/src/include/nodes/relation.h b/src/include/nodes/relation.h index 14fcb5c0e97..681a2c8a6ad 100644 --- a/src/include/nodes/relation.h +++ b/src/include/nodes/relation.h @@ -117,7 +117,7 @@ typedef struct PlannerGlobal * * This struct is conventionally called "root" in all the planner routines. * It holds links to all of the planner's working state, in addition to the - * original Query. Note that at present the planner extensively modifies + * original Query. Note that at present the planner extensively modifies * the passed-in Query data structure; someday that should stop. *---------- */ @@ -135,7 +135,7 @@ typedef struct PlannerInfo /* * simple_rel_array holds pointers to "base rels" and "other rels" (see - * comments for RelOptInfo for more info). It is indexed by rangetable + * comments for RelOptInfo for more info). It is indexed by rangetable * index (so entry 0 is always wasted). Entries can be NULL when an RTE * does not correspond to a base relation, such as a join RTE or an * unreferenced view RTE; or if the RelOptInfo hasn't been made yet. @@ -156,7 +156,7 @@ typedef struct PlannerInfo * considered in this planning run. For small problems we just scan the * list to do lookups, but when there are many join relations we build a * hash table for faster lookups. The hash table is present and valid - * when join_rel_hash is not NULL. Note that we still maintain the list + * when join_rel_hash is not NULL. Note that we still maintain the list * even when using the hash table for lookups; this simplifies life for * GEQO. */ @@ -278,7 +278,7 @@ typedef struct PlannerInfo * Currently the only kind of otherrels are those made for member relations * of an "append relation", that is an inheritance set or UNION ALL subquery. * An append relation has a parent RTE that is a base rel, which represents - * the entire append relation. The member RTEs are otherrels. The parent + * the entire append relation. The member RTEs are otherrels. The parent * is present in the query join tree but the members are not. The member * RTEs and otherrels are used to plan the scans of the individual tables or * subqueries of the append set; then the parent baserel is given Append @@ -290,7 +290,7 @@ typedef struct PlannerInfo * alias Vars are expanded to non-aliased form during preprocess_expression. * * Parts of this data structure are specific to various scan and join - * mechanisms. It didn't seem worth creating new node types for them. + * mechanisms. It didn't seem worth creating new node types for them. * * relids - Set of base-relation identifiers; it is a base relation * if there is just one, a join relation if more than one @@ -515,7 +515,7 @@ typedef struct IndexOptInfo * equal to each other, where "equal" is according to the rules of the btree * operator family(s) shown in ec_opfamilies, as well as the collation shown * by ec_collation. (We restrict an EC to contain only equalities whose - * operators belong to the same set of opfamilies. This could probably be + * operators belong to the same set of opfamilies. This could probably be * relaxed, but for now it's not worth the trouble, since nearly all equality * operators belong to only one btree opclass anyway. Similarly, we suppose * that all or none of the input datatypes are collatable, so that a single @@ -525,7 +525,7 @@ typedef struct IndexOptInfo * us represent knowledge about different sort orderings being equivalent. * Since every PathKey must reference an EquivalenceClass, we will end up * with single-member EquivalenceClasses whenever a sort key expression has - * not been equivalenced to anything else. It is also possible that such an + * not been equivalenced to anything else. It is also possible that such an * EquivalenceClass will contain a volatile expression ("ORDER BY random()"), * which is a case that can't arise otherwise since clauses containing * volatile functions are never considered mergejoinable. We mark such @@ -538,7 +538,7 @@ typedef struct IndexOptInfo * We allow equality clauses appearing below the nullable side of an outer join * to form EquivalenceClasses, but these have a slightly different meaning: * the included values might be all NULL rather than all the same non-null - * values. See src/backend/optimizer/README for more on that point. + * values. See src/backend/optimizer/README for more on that point. * * NB: if ec_merged isn't NULL, this class has been merged into another, and * should be ignored in favor of using the pointed-to class. @@ -587,7 +587,7 @@ typedef struct EquivalenceClass * * em_datatype is usually the same as exprType(em_expr), but can be * different when dealing with a binary-compatible opfamily; in particular - * anyarray_ops would never work without this. Use em_datatype when + * anyarray_ops would never work without this. Use em_datatype when * looking up a specific btree operator to work with this expression. */ typedef struct EquivalenceMember @@ -616,7 +616,7 @@ typedef struct EquivalenceMember * information.) * * Note: pk_strategy is either BTLessStrategyNumber (for ASC) or - * BTGreaterStrategyNumber (for DESC). We assume that all ordering-capable + * BTGreaterStrategyNumber (for DESC). We assume that all ordering-capable * index types will use btree-compatible strategy numbers. */ @@ -728,11 +728,11 @@ typedef struct IndexPath * * The individual indexscans are represented by IndexPath nodes, and any * logic on top of them is represented by a tree of BitmapAndPath and - * BitmapOrPath nodes. Notice that we can use the same IndexPath node both + * BitmapOrPath nodes. Notice that we can use the same IndexPath node both * to represent a regular IndexScan plan, and as the child of a BitmapHeapPath * that represents scanning the same index using a BitmapIndexScan. The * startup_cost and total_cost figures of an IndexPath always represent the - * costs to use it as a regular IndexScan. The costs of a BitmapIndexScan + * costs to use it as a regular IndexScan. The costs of a BitmapIndexScan * can be computed using the IndexPath's indextotalcost and indexselectivity. * * BitmapHeapPaths can be nestloop inner indexscans. The isjoininner and @@ -855,7 +855,7 @@ typedef struct MaterialPath * * This is unlike the other Path nodes in that it can actually generate * different plans: either hash-based or sort-based implementation, or a - * no-op if the input path can be proven distinct already. The decision + * no-op if the input path can be proven distinct already. The decision * is sufficiently localized that it's not worth having separate Path node * types. (Note: in the no-op case, we could eliminate the UniquePath node * entirely and just return the subpath; but it's convenient to have a @@ -981,7 +981,7 @@ typedef struct HashPath * When we construct a join rel that includes all the base rels referenced * in a multi-relation restriction clause, we place that clause into the * joinrestrictinfo lists of paths for the join rel, if neither left nor - * right sub-path includes all base rels referenced in the clause. The clause + * right sub-path includes all base rels referenced in the clause. The clause * will be applied at that join level, and will not propagate any further up * the join tree. (Note: the "predicate migration" code was once intended to * push restriction clauses up and down the plan tree based on evaluation @@ -1021,13 +1021,13 @@ typedef struct HashPath * that appeared elsewhere in the tree and were pushed down to the join rel * because they used no other rels. That's what the is_pushed_down flag is * for; it tells us that a qual is not an OUTER JOIN qual for the set of base - * rels listed in required_relids. A clause that originally came from WHERE + * rels listed in required_relids. A clause that originally came from WHERE * or an INNER JOIN condition will *always* have its is_pushed_down flag set. * It's possible for an OUTER JOIN clause to be marked is_pushed_down too, * if we decide that it can be pushed down into the nullable side of the join. * In that case it acts as a plain filter qual for wherever it gets evaluated. * (In short, is_pushed_down is only false for non-degenerate outer join - * conditions. Possibly we should rename it to reflect that meaning?) + * conditions. Possibly we should rename it to reflect that meaning?) * * RestrictInfo nodes also contain an outerjoin_delayed flag, which is true * if the clause's applicability must be delayed due to any outer joins @@ -1037,10 +1037,10 @@ typedef struct HashPath * forced null by some outer join below the clause. outerjoin_delayed = true * is subtly different from nullable_relids != NULL: a clause might reference * some nullable rels and yet not be outerjoin_delayed because it also - * references all the other rels of the outer join(s). A clause that is not + * references all the other rels of the outer join(s). A clause that is not * outerjoin_delayed can be enforced anywhere it is computable. * - * In general, the referenced clause might be arbitrarily complex. The + * In general, the referenced clause might be arbitrarily complex. The * kinds of clauses we can handle as indexscan quals, mergejoin clauses, * or hashjoin clauses are limited (e.g., no volatile functions). The code * for each kind of path is responsible for identifying the restrict clauses @@ -1065,7 +1065,7 @@ typedef struct HashPath * * The pseudoconstant flag is set true if the clause contains no Vars of * the current query level and no volatile functions. Such a clause can be - * pulled out and used as a one-time qual in a gating Result node. We keep + * pulled out and used as a one-time qual in a gating Result node. We keep * pseudoconstant clauses in the same lists as other RestrictInfos so that * the regular clause-pushing machinery can assign them to the correct join * level, but they need to be treated specially for cost and selectivity @@ -1075,7 +1075,7 @@ typedef struct HashPath * * When join clauses are generated from EquivalenceClasses, there may be * several equally valid ways to enforce join equivalence, of which we need - * apply only one. We mark clauses of this kind by setting parent_ec to + * apply only one. We mark clauses of this kind by setting parent_ec to * point to the generating EquivalenceClass. Multiple clauses with the same * parent_ec in the same join are redundant. */ @@ -1201,8 +1201,8 @@ typedef struct InnerIndexscanInfo /* * Placeholder node for an expression to be evaluated below the top level - * of a plan tree. This is used during planning to represent the contained - * expression. At the end of the planning process it is replaced by either + * of a plan tree. This is used during planning to represent the contained + * expression. At the end of the planning process it is replaced by either * the contained expression or a Var referring to a lower-level evaluation of * the contained expression. Typically the evaluation occurs below an outer * join, and Var references above the outer join might thereby yield NULL @@ -1226,9 +1226,9 @@ typedef struct PlaceHolderVar * "Special join" info. * * One-sided outer joins constrain the order of joining partially but not - * completely. We flatten such joins into the planner's top-level list of + * completely. We flatten such joins into the planner's top-level list of * relations to join, but record information about each outer join in a - * SpecialJoinInfo struct. These structs are kept in the PlannerInfo node's + * SpecialJoinInfo struct. These structs are kept in the PlannerInfo node's * join_info_list. * * Similarly, semijoins and antijoins created by flattening IN (subselect) @@ -1256,7 +1256,7 @@ typedef struct PlaceHolderVar * to be evaluated after this join is formed (because it references the RHS). * Any outer joins that have such a clause and this join in their RHS cannot * commute with this join, because that would leave noplace to check the - * pushed-down clause. (We don't track this for FULL JOINs, either.) + * pushed-down clause. (We don't track this for FULL JOINs, either.) * * join_quals is an implicit-AND list of the quals syntactically associated * with the join (they may or may not end up being applied at the join level). @@ -1341,7 +1341,7 @@ typedef struct AppendRelInfo /* * For an inheritance appendrel, the parent and child are both regular * relations, and we store their rowtype OIDs here for use in translating - * whole-row Vars. For a UNION-ALL appendrel, the parent and child are + * whole-row Vars. For a UNION-ALL appendrel, the parent and child are * both subqueries with no named rowtype, and we store InvalidOid here. */ Oid parent_reltype; /* OID of parent's composite type */ @@ -1353,14 +1353,14 @@ typedef struct AppendRelInfo * used to translate Vars referencing the parent rel into references to * the child. A list element is NULL if it corresponds to a dropped * column of the parent (this is only possible for inheritance cases, not - * UNION ALL). The list elements are always simple Vars for inheritance + * UNION ALL). The list elements are always simple Vars for inheritance * cases, but can be arbitrary expressions in UNION ALL cases. * * Notice we only store entries for user columns (attno > 0). Whole-row * Vars are special-cased, and system columns (attno < 0) need no special * translation since their attnos are the same for all tables. * - * Caution: the Vars have varlevelsup = 0. Be careful to adjust as needed + * Caution: the Vars have varlevelsup = 0. Be careful to adjust as needed * when copying into a subquery. */ List *translated_vars; /* Expressions in the child's Vars */ @@ -1377,7 +1377,7 @@ typedef struct AppendRelInfo * For each distinct placeholder expression generated during planning, we * store a PlaceHolderInfo node in the PlannerInfo node's placeholder_list. * This stores info that is needed centrally rather than in each copy of the - * PlaceHolderVar. The phid fields identify which PlaceHolderInfo goes with + * PlaceHolderVar. The phid fields identify which PlaceHolderInfo goes with * each PlaceHolderVar. Note that phid is unique throughout a planner run, * not just within a query level --- this is so that we need not reassign ID's * when pulling a subquery into its parent. |