Fix parallel restore of FKs to partitioned tables

When an FK constraint is created, it needs the index on the referenced
table to exist and be valid.  When doing parallel pg_restore and the
referenced table was partitioned, this condition can sometimes not be
met, because pg_dump didn't emit sufficient object dependencies to
ensure so; this means that parallel pg_restore would fail in certain
conditions.  Fix by having pg_dump make the FK constraint object
dependent on the partition attachment objects for the constraint's
referenced index.

This has been broken since f56f8f8da6af, so backpatch to Postgres 12.

Discussion: https://postgr.es/m/20191005224333[email protected]

diff --git a/src/bin/pg_dump/common.c b/src/bin/pg_dump/common.c
index 02a865f456fbf7cc212f7199d6b0ae86e2eebfdb..3549f7bc082857ca41e47fd639d0b1b329736c68 100644 (file)
--- a/src/bin/pg_dump/common.c
+++ b/src/bin/pg_dump/common.c
@@ -412,6 +412,9 @@ flagInhIndexes(Archive *fout, TableInfo tblinfo[], int numTables)
            addObjectDependency(&attachinfo[k].dobj,
                                parentidx->indextable->dobj.dumpId);
 
+           /* keep track of the list of partitions in the parent index */
+           simple_ptr_list_append(&parentidx->partattaches, &attachinfo[k].dobj);
+
            k++;
        }
    }

diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c
index a9c868b9aff46d423e1358264f846a6ce9518713..33e58fa287e7c4a2c10dfe177be49218844c157d 100644 (file)
--- a/src/bin/pg_dump/pg_dump.c
+++ b/src/bin/pg_dump/pg_dump.c
@@ -7109,6 +7109,7 @@ getIndexes(Archive *fout, TableInfo tblinfo[], int numTables)
            indxinfo[j].indisclustered = (PQgetvalue(res, j, i_indisclustered)[0] == 't');
            indxinfo[j].indisreplident = (PQgetvalue(res, j, i_indisreplident)[0] == 't');
            indxinfo[j].parentidx = atooid(PQgetvalue(res, j, i_parentidx));
+           indxinfo[j].partattaches = (SimplePtrList) { NULL, NULL };
            contype = *(PQgetvalue(res, j, i_contype));
 
            if (contype == 'p' || contype == 'u' || contype == 'x')
@@ -7241,6 +7242,7 @@ getConstraints(Archive *fout, TableInfo tblinfo[], int numTables)
                i_conoid,
                i_conname,
                i_confrelid,
+               i_conindid,
                i_condef;
    int         ntups;
 
@@ -7266,7 +7268,7 @@ getConstraints(Archive *fout, TableInfo tblinfo[], int numTables)
        resetPQExpBuffer(query);
        if (fout->remoteVersion >= 110000)
            appendPQExpBuffer(query,
-                             "SELECT tableoid, oid, conname, confrelid, "
+                             "SELECT tableoid, oid, conname, confrelid, conindid, "
                              "pg_catalog.pg_get_constraintdef(oid) AS condef "
                              "FROM pg_catalog.pg_constraint "
                              "WHERE conrelid = '%u'::pg_catalog.oid "
@@ -7275,7 +7277,7 @@ getConstraints(Archive *fout, TableInfo tblinfo[], int numTables)
                              tbinfo->dobj.catId.oid);
        else
            appendPQExpBuffer(query,
-                             "SELECT tableoid, oid, conname, confrelid, "
+                             "SELECT tableoid, oid, conname, confrelid, 0 as conindid, "
                              "pg_catalog.pg_get_constraintdef(oid) AS condef "
                              "FROM pg_catalog.pg_constraint "
                              "WHERE conrelid = '%u'::pg_catalog.oid "
@@ -7289,12 +7291,15 @@ getConstraints(Archive *fout, TableInfo tblinfo[], int numTables)
        i_conoid = PQfnumber(res, "oid");
        i_conname = PQfnumber(res, "conname");
        i_confrelid = PQfnumber(res, "confrelid");
+       i_conindid = PQfnumber(res, "conindid");
        i_condef = PQfnumber(res, "condef");
 
        constrinfo = (ConstraintInfo *) pg_malloc(ntups * sizeof(ConstraintInfo));
 
        for (j = 0; j < ntups; j++)
        {
+           TableInfo *reftable;
+
            constrinfo[j].dobj.objType = DO_FK_CONSTRAINT;
            constrinfo[j].dobj.catId.tableoid = atooid(PQgetvalue(res, j, i_contableoid));
            constrinfo[j].dobj.catId.oid = atooid(PQgetvalue(res, j, i_conoid));
@@ -7311,6 +7316,39 @@ getConstraints(Archive *fout, TableInfo tblinfo[], int numTables)
            constrinfo[j].condeferred = false;
            constrinfo[j].conislocal = true;
            constrinfo[j].separate = true;
+
+           /*
+            * Restoring an FK that points to a partitioned table requires
+            * that all partition indexes have been attached beforehand.
+            * Ensure that happens by making the constraint depend on each
+            * index partition attach object.
+            */
+           reftable = findTableByOid(constrinfo[j].confrelid);
+           if (reftable && reftable->relkind == RELKIND_PARTITIONED_TABLE)
+           {
+               IndxInfo   *refidx;
+               Oid         indexOid = atooid(PQgetvalue(res, j, i_conindid));
+
+               if (indexOid != InvalidOid)
+               {
+                   for (int k = 0; k < reftable->numIndexes; k++)
+                   {
+                       SimplePtrListCell *cell;
+
+                       /* not our index? */
+                       if (reftable->indexes[k].dobj.catId.oid != indexOid)
+                           continue;
+
+                       refidx = &reftable->indexes[k];
+                       for (cell = refidx->partattaches.head; cell;
+                            cell = cell->next)
+                           addObjectDependency(&constrinfo[j].dobj,
+                                               ((DumpableObject *)
+                                                cell->ptr)->dumpId);
+                       break;
+                   }
+               }
+           }
        }
 
        PQclear(res);

diff --git a/src/bin/pg_dump/pg_dump.h b/src/bin/pg_dump/pg_dump.h
index c3c2ea147369bb04a9fcd97eee23fe7bf75a6d58..ce04f914e1d3584e3806321ab0a2f23319efe0e6 100644 (file)
--- a/src/bin/pg_dump/pg_dump.h
+++ b/src/bin/pg_dump/pg_dump.h
@@ -371,6 +371,8 @@ typedef struct _indxInfo
    bool        indisclustered;
    bool        indisreplident;
    Oid         parentidx;      /* if partitioned, parent index OID */
+   SimplePtrList partattaches; /* if partitioned, partition attach objects */
+
    /* if there is an associated constraint object, its dumpId: */
    DumpId      indexconstraint;
 } IndxInfo;

diff --git a/src/fe_utils/simple_list.c b/src/fe_utils/simple_list.c
index 8d605140a742e14fdca2203631042643829e70ca..2232e8db73ef501f2972ab769afa3ad40cd575a1 100644 (file)
--- a/src/fe_utils/simple_list.c
+++ b/src/fe_utils/simple_list.c
@@ -114,3 +114,24 @@ simple_string_list_not_touched(SimpleStringList *list)
    }
    return NULL;
 }
+
+/*
+ * Append a pointer to the list.
+ *
+ * Caller must ensure that the pointer remains valid.
+ */
+void
+simple_ptr_list_append(SimplePtrList *list, void *ptr)
+{
+   SimplePtrListCell *cell;
+
+   cell = (SimplePtrListCell *) pg_malloc(sizeof(SimplePtrListCell));
+   cell->next = NULL;
+   cell->ptr = ptr;
+
+   if (list->tail)
+       list->tail->next = cell;
+   else
+       list->head = cell;
+   list->tail = cell;
+}

diff --git a/src/include/fe_utils/simple_list.h b/src/include/fe_utils/simple_list.h
index 8a95cbb3a85b7ba696b9170aa464b0621d96b9e3..04dfa2cecfb4e3cb5bac976b5e6037f2c247df9b 100644 (file)
--- a/src/include/fe_utils/simple_list.h
+++ b/src/include/fe_utils/simple_list.h
@@ -2,9 +2,9 @@
  *
  * Simple list facilities for frontend code
  *
- * Data structures for simple lists of OIDs and strings.  The support for
- * these is very primitive compared to the backend's List facilities, but
- * it's all we need in, eg, pg_dump.
+ * Data structures for simple lists of OIDs, strings, and pointers.  The
+ * support for these is very primitive compared to the backend's List
+ * facilities, but it's all we need in, eg, pg_dump.
  *
  *
  * Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
@@ -43,6 +43,17 @@ typedef struct SimpleStringList
    SimpleStringListCell *tail;
 } SimpleStringList;
 
+typedef struct SimplePtrListCell
+{
+   struct SimplePtrListCell *next;
+   void       *ptr;
+} SimplePtrListCell;
+
+typedef struct SimplePtrList
+{
+   SimplePtrListCell *head;
+   SimplePtrListCell *tail;
+} SimplePtrList;
 
 extern void simple_oid_list_append(SimpleOidList *list, Oid val);
 extern bool simple_oid_list_member(SimpleOidList *list, Oid val);
@@ -52,4 +63,6 @@ extern bool simple_string_list_member(SimpleStringList *list, const char *val);
 
 extern const char *simple_string_list_not_touched(SimpleStringList *list);
 
+extern void simple_ptr_list_append(SimplePtrList *list, void *val);
+
 #endif                         /* SIMPLE_LIST_H */