Refactor planner's header files.

Create a new header optimizer/optimizer.h, which exposes just the
planner functions that can be used "at arm's length", without need
to access Paths or the other planner-internal data structures defined
in nodes/relation.h.  This is intended to provide the whole planner
API seen by most of the rest of the system; although FDWs still need
to use additional stuff, and more thought is also needed about just
what selfuncs.c should rely on.

The main point of doing this now is to limit the amount of new
#include baggage that will be needed by "planner support functions",
which I expect to introduce later, and which will be in relevant
datatype modules rather than anywhere near the planner.

This commit just moves relevant declarations into optimizer.h from
other header files (a couple of which go away because everything
got moved), and adjusts #include lists to match.  There's further
cleanup that could be done if we want to decide that some stuff
being exposed by optimizer.h doesn't belong in the planner at all,
but I'll leave that for another day.

Discussion: https://postgr.es/m/[email protected]

contrib/bloom/blcost.c

@@ -13,7 +13,6 @@
 #include "postgres.h"
 
 #include "fmgr.h"
-#include "optimizer/cost.h"
 #include "utils/selfuncs.h"
 
 #include "bloom.h"

contrib/file_fdw/file_fdw.c

@@ -29,11 +29,10 @@
 #include "foreign/foreign.h"
 #include "miscadmin.h"
 #include "nodes/makefuncs.h"
-#include "optimizer/cost.h"
+#include "optimizer/optimizer.h"
 #include "optimizer/pathnode.h"
 #include "optimizer/planmain.h"
 #include "optimizer/restrictinfo.h"
-#include "optimizer/var.h"
 #include "utils/memutils.h"
 #include "utils/rel.h"
 #include "utils/sampling.h"

contrib/postgres_fdw/deparse.c

@@ -48,10 +48,9 @@
 #include "nodes/makefuncs.h"
 #include "nodes/nodeFuncs.h"
 #include "nodes/plannodes.h"
-#include "optimizer/clauses.h"
+#include "optimizer/optimizer.h"
 #include "optimizer/prep.h"
 #include "optimizer/tlist.h"
-#include "optimizer/var.h"
 #include "parser/parsetree.h"
 #include "utils/builtins.h"
 #include "utils/lsyscache.h"

contrib/postgres_fdw/postgres_fdw.c

@@ -28,11 +28,11 @@
 #include "nodes/nodeFuncs.h"
 #include "optimizer/cost.h"
 #include "optimizer/clauses.h"
+#include "optimizer/optimizer.h"
 #include "optimizer/pathnode.h"
 #include "optimizer/paths.h"
 #include "optimizer/planmain.h"
 #include "optimizer/restrictinfo.h"
-#include "optimizer/var.h"
 #include "optimizer/tlist.h"
 #include "parser/parsetree.h"
 #include "utils/builtins.h"

contrib/tsm_system_rows/tsm_system_rows.c

@@ -33,8 +33,7 @@
 #include "access/tsmapi.h"
 #include "catalog/pg_type.h"
 #include "miscadmin.h"
-#include "optimizer/clauses.h"
-#include "optimizer/cost.h"
+#include "optimizer/optimizer.h"
 #include "utils/sampling.h"
 
 PG_MODULE_MAGIC;

contrib/tsm_system_time/tsm_system_time.c

@@ -31,8 +31,7 @@
 #include "access/tsmapi.h"
 #include "catalog/pg_type.h"
 #include "miscadmin.h"
-#include "optimizer/clauses.h"
-#include "optimizer/cost.h"
+#include "optimizer/optimizer.h"
 #include "utils/sampling.h"
 #include "utils/spccache.h"
 

src/backend/access/gist/gistbuild.c

@@ -22,7 +22,7 @@
 #include "access/xloginsert.h"
 #include "catalog/index.h"
 #include "miscadmin.h"
-#include "optimizer/cost.h"
+#include "optimizer/optimizer.h"
 #include "storage/bufmgr.h"
 #include "storage/smgr.h"
 #include "utils/memutils.h"

src/backend/access/spgist/spgutils.c

@@ -22,7 +22,6 @@
 #include "access/transam.h"
 #include "access/xact.h"
 #include "catalog/pg_amop.h"
-#include "optimizer/paths.h"
 #include "storage/bufmgr.h"
 #include "storage/indexfsm.h"
 #include "storage/lmgr.h"
@@ -32,9 +31,6 @@
 #include "utils/lsyscache.h"
 #include "utils/syscache.h"
 
-extern Expr *spgcanorderbyop(IndexOptInfo *index,
-				PathKey *pathkey, int pathkeyno,
-				Expr *orderby_clause, int *indexcol_p);
 
 /*
  * SP-GiST handler function: return IndexAmRoutine with access method parameters

src/backend/access/tablesample/bernoulli.c

@@ -29,8 +29,7 @@
 #include "access/hash.h"
 #include "access/tsmapi.h"
 #include "catalog/pg_type.h"
-#include "optimizer/clauses.h"
-#include "optimizer/cost.h"
+#include "optimizer/optimizer.h"
 #include "utils/builtins.h"
 
 

src/backend/access/tablesample/system.c

@@ -31,8 +31,7 @@
 #include "access/relscan.h"
 #include "access/tsmapi.h"
 #include "catalog/pg_type.h"
-#include "optimizer/clauses.h"
-#include "optimizer/cost.h"
+#include "optimizer/optimizer.h"
 #include "utils/builtins.h"
 
 

src/backend/access/transam/parallel.c

@@ -28,7 +28,7 @@
 #include "libpq/pqformat.h"
 #include "libpq/pqmq.h"
 #include "miscadmin.h"
-#include "optimizer/planmain.h"
+#include "optimizer/optimizer.h"
 #include "pgstat.h"
 #include "storage/ipc.h"
 #include "storage/sinval.h"

src/backend/catalog/heap.c

@@ -64,9 +64,7 @@
 #include "executor/executor.h"
 #include "miscadmin.h"
 #include "nodes/nodeFuncs.h"
-#include "optimizer/clauses.h"
-#include "optimizer/var.h"
-#include "optimizer/planner.h"
+#include "optimizer/optimizer.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"

src/backend/catalog/index.c

@@ -56,8 +56,7 @@
 #include "miscadmin.h"
 #include "nodes/makefuncs.h"
 #include "nodes/nodeFuncs.h"
-#include "optimizer/clauses.h"
-#include "optimizer/planner.h"
+#include "optimizer/optimizer.h"
 #include "parser/parser.h"
 #include "rewrite/rewriteManip.h"
 #include "storage/bufmgr.h"

src/backend/catalog/partition.c

@@ -24,9 +24,7 @@
 #include "catalog/pg_inherits.h"
 #include "catalog/pg_partitioned_table.h"
 #include "nodes/makefuncs.h"
-#include "optimizer/clauses.h"
-#include "optimizer/prep.h"
-#include "optimizer/var.h"
+#include "optimizer/optimizer.h"
 #include "partitioning/partbounds.h"
 #include "rewrite/rewriteManip.h"
 #include "utils/fmgroids.h"

src/backend/commands/cluster.c

@@ -38,7 +38,7 @@
 #include "commands/tablecmds.h"
 #include "commands/vacuum.h"
 #include "miscadmin.h"
-#include "optimizer/planner.h"
+#include "optimizer/optimizer.h"
 #include "storage/bufmgr.h"
 #include "storage/lmgr.h"
 #include "storage/predicate.h"

src/backend/commands/copy.c

@@ -37,9 +37,7 @@
 #include "libpq/pqformat.h"
 #include "mb/pg_wchar.h"
 #include "miscadmin.h"
-#include "optimizer/clauses.h"
-#include "optimizer/planner.h"
-#include "optimizer/prep.h"
+#include "optimizer/optimizer.h"
 #include "nodes/makefuncs.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"

src/backend/commands/explain.c

@@ -24,8 +24,6 @@
 #include "nodes/extensible.h"
 #include "nodes/makefuncs.h"
 #include "nodes/nodeFuncs.h"
-#include "optimizer/clauses.h"
-#include "optimizer/planmain.h"
 #include "parser/parsetree.h"
 #include "rewrite/rewriteHandler.h"
 #include "storage/bufmgr.h"

src/backend/commands/functioncmds.c

@@ -54,8 +54,7 @@
 #include "executor/executor.h"
 #include "funcapi.h"
 #include "miscadmin.h"
-#include "optimizer/clauses.h"
-#include "optimizer/var.h"
+#include "optimizer/optimizer.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"

src/backend/commands/indexcmds.c

@@ -42,9 +42,7 @@
 #include "miscadmin.h"
 #include "nodes/makefuncs.h"
 #include "nodes/nodeFuncs.h"
-#include "optimizer/clauses.h"
-#include "optimizer/planner.h"
-#include "optimizer/var.h"
+#include "optimizer/optimizer.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_func.h"
 #include "parser/parse_oper.h"

src/backend/commands/tablecmds.c

@@ -63,11 +63,7 @@
 #include "nodes/makefuncs.h"
 #include "nodes/nodeFuncs.h"
 #include "nodes/parsenodes.h"
-#include "optimizer/clauses.h"
-#include "optimizer/planner.h"
-#include "optimizer/predtest.h"
-#include "optimizer/prep.h"
-#include "optimizer/var.h"
+#include "optimizer/optimizer.h"
 #include "parser/parse_clause.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"

src/backend/commands/trigger.c

@@ -36,8 +36,7 @@
 #include "miscadmin.h"
 #include "nodes/bitmapset.h"
 #include "nodes/makefuncs.h"
-#include "optimizer/clauses.h"
-#include "optimizer/var.h"
+#include "optimizer/optimizer.h"
 #include "parser/parse_clause.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_func.h"

src/backend/commands/typecmds.c

@@ -56,7 +56,7 @@
 #include "executor/executor.h"
 #include "miscadmin.h"
 #include "nodes/makefuncs.h"
-#include "optimizer/var.h"
+#include "optimizer/optimizer.h"
 #include "parser/parse_coerce.h"
 #include "parser/parse_collate.h"
 #include "parser/parse_expr.h"

src/backend/executor/execExpr.c

@@ -40,8 +40,7 @@
 #include "miscadmin.h"
 #include "nodes/makefuncs.h"
 #include "nodes/nodeFuncs.h"
-#include "optimizer/clauses.h"
-#include "optimizer/planner.h"
+#include "optimizer/optimizer.h"
 #include "pgstat.h"
 #include "utils/builtins.h"
 #include "utils/datum.h"

src/backend/executor/execMain.c

@@ -52,7 +52,6 @@
 #include "jit/jit.h"
 #include "mb/pg_wchar.h"
 #include "miscadmin.h"
-#include "optimizer/clauses.h"
 #include "parser/parsetree.h"
 #include "rewrite/rewriteManip.h"
 #include "storage/bufmgr.h"

src/backend/executor/execParallel.c

@@ -39,8 +39,6 @@
 #include "executor/tqueue.h"
 #include "jit/jit.h"
 #include "nodes/nodeFuncs.h"
-#include "optimizer/planmain.h"
-#include "optimizer/planner.h"
 #include "storage/spin.h"
 #include "tcop/tcopprot.h"
 #include "utils/datum.h"

src/backend/executor/nodeAgg.c

@@ -226,8 +226,7 @@
 #include "miscadmin.h"
 #include "nodes/makefuncs.h"
 #include "nodes/nodeFuncs.h"
-#include "optimizer/clauses.h"
-#include "optimizer/tlist.h"
+#include "optimizer/optimizer.h"
 #include "parser/parse_agg.h"
 #include "parser/parse_coerce.h"
 #include "utils/acl.h"

src/backend/executor/nodeGather.c

@@ -38,7 +38,7 @@
 #include "executor/nodeSubplan.h"
 #include "executor/tqueue.h"
 #include "miscadmin.h"
-#include "optimizer/planmain.h"
+#include "optimizer/optimizer.h"
 #include "pgstat.h"
 #include "utils/memutils.h"
 #include "utils/rel.h"

src/backend/executor/nodeGatherMerge.c

@@ -23,7 +23,7 @@
 #include "executor/tqueue.h"
 #include "lib/binaryheap.h"
 #include "miscadmin.h"
-#include "optimizer/planmain.h"
+#include "optimizer/optimizer.h"
 #include "utils/memutils.h"
 #include "utils/rel.h"
 

src/backend/executor/nodeIndexscan.c

@@ -37,7 +37,6 @@
 #include "lib/pairingheap.h"
 #include "miscadmin.h"
 #include "nodes/nodeFuncs.h"
-#include "optimizer/clauses.h"
 #include "utils/array.h"
 #include "utils/datum.h"
 #include "utils/lsyscache.h"

src/backend/executor/nodeWindowAgg.c

@@ -41,7 +41,7 @@
 #include "executor/nodeWindowAgg.h"
 #include "miscadmin.h"
 #include "nodes/nodeFuncs.h"
-#include "optimizer/clauses.h"
+#include "optimizer/optimizer.h"
 #include "parser/parse_agg.h"
 #include "parser/parse_coerce.h"
 #include "utils/acl.h"

src/backend/jit/llvm/llvmjit_expr.c

@@ -33,7 +33,6 @@
 #include "miscadmin.h"
 #include "nodes/makefuncs.h"
 #include "nodes/nodeFuncs.h"
-#include "optimizer/planner.h"
 #include "parser/parse_coerce.h"
 #include "parser/parsetree.h"
 #include "pgstat.h"

src/backend/optimizer/path/allpaths.c

@@ -35,13 +35,13 @@
 #include "optimizer/cost.h"
 #include "optimizer/geqo.h"
 #include "optimizer/inherit.h"
+#include "optimizer/optimizer.h"
 #include "optimizer/pathnode.h"
 #include "optimizer/paths.h"
 #include "optimizer/plancat.h"
 #include "optimizer/planner.h"
 #include "optimizer/restrictinfo.h"
 #include "optimizer/tlist.h"
-#include "optimizer/var.h"
 #include "parser/parse_clause.h"
 #include "parser/parsetree.h"
 #include "partitioning/partprune.h"

src/backend/optimizer/path/clausesel.c

@@ -18,6 +18,7 @@
 #include "nodes/nodeFuncs.h"
 #include "optimizer/clauses.h"
 #include "optimizer/cost.h"
+#include "optimizer/optimizer.h"
 #include "optimizer/pathnode.h"
 #include "optimizer/plancat.h"
 #include "utils/fmgroids.h"

src/backend/optimizer/path/costsize.c

@@ -83,6 +83,7 @@
 #include "nodes/nodeFuncs.h"
 #include "optimizer/clauses.h"
 #include "optimizer/cost.h"
+#include "optimizer/optimizer.h"
 #include "optimizer/pathnode.h"
 #include "optimizer/paths.h"
 #include "optimizer/placeholder.h"

src/backend/optimizer/path/equivclass.c

@@ -24,11 +24,11 @@
 #include "nodes/nodeFuncs.h"
 #include "optimizer/appendinfo.h"
 #include "optimizer/clauses.h"
+#include "optimizer/optimizer.h"
 #include "optimizer/pathnode.h"
 #include "optimizer/paths.h"
 #include "optimizer/planmain.h"
 #include "optimizer/restrictinfo.h"
-#include "optimizer/var.h"
 #include "utils/lsyscache.h"
 
 

src/backend/optimizer/path/indxpath.c

@@ -28,12 +28,11 @@
 #include "nodes/nodeFuncs.h"
 #include "optimizer/clauses.h"
 #include "optimizer/cost.h"
+#include "optimizer/optimizer.h"
 #include "optimizer/pathnode.h"
 #include "optimizer/paths.h"
-#include "optimizer/predtest.h"
 #include "optimizer/prep.h"
 #include "optimizer/restrictinfo.h"
-#include "optimizer/var.h"
 #include "utils/builtins.h"
 #include "utils/bytea.h"
 #include "utils/lsyscache.h"

src/backend/optimizer/path/pathkeys.c

@@ -21,10 +21,9 @@
 #include "nodes/makefuncs.h"
 #include "nodes/nodeFuncs.h"
 #include "nodes/plannodes.h"
-#include "optimizer/clauses.h"
+#include "optimizer/optimizer.h"
 #include "optimizer/pathnode.h"
 #include "optimizer/paths.h"
-#include "optimizer/tlist.h"
 #include "utils/lsyscache.h"
 
 

src/backend/optimizer/path/tidpath.c

@@ -40,10 +40,10 @@
 #include "catalog/pg_type.h"
 #include "nodes/nodeFuncs.h"
 #include "optimizer/clauses.h"
+#include "optimizer/optimizer.h"
 #include "optimizer/pathnode.h"
 #include "optimizer/paths.h"
 #include "optimizer/restrictinfo.h"
-#include "optimizer/var.h"
 
 
 /*