pg_dump: Add a --load-via-partition-root option.

Rushabh Lathia, reviewed and somewhat revised by me.  Testing by
Rajkumar Raghuwanshi.

Discussion: http://postgr.es/m/CAGPqQf0C1he087bz9xRBOGZBuESYz9X=Fp8Ca_g+TfHgAff75g@mail.gmail.com

diff --git a/doc/src/sgml/ref/pg_dump.sgml b/doc/src/sgml/ref/pg_dump.sgml
index bafa031e1a8ec4b674260c03da3b5b74663a911e..ad5b6fc703587290840730e46e941d9b6b0ee9a1 100644 (file)
--- a/doc/src/sgml/ref/pg_dump.sgml
+++ b/doc/src/sgml/ref/pg_dump.sgml
@@ -888,6 +888,21 @@ PostgreSQL documentation
       </listitem>
      </varlistentry>
 
+     <varlistentry>
+      <term><option>--load-via-partition-root</></term>
+      <listitem>
+       <para>
+        When dumping a COPY or INSERT statement for a partitioned table,
+        target the root of the partitioning hierarchy which contains it rather
+        than the partition itself.  This may be useful when reloading data on
+        a server where rows do not always fall into the same partitions as
+        they did on the original server.  This could happen, for example, if
+        the partitioning column is of type text and the two system have
+        different definitions of the collation used to partition the data.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry>
        <term><option>--section=<replaceable class="parameter">sectionname</replaceable></option></term>
        <listitem>

diff --git a/doc/src/sgml/ref/pg_dumpall.sgml b/doc/src/sgml/ref/pg_dumpall.sgml
index aa944a2e92ad074d92687dd194e4ecb9ae368664..f8a2521743fb7e71e90bd7fdf2825f85d9a612cc 100644 (file)
--- a/doc/src/sgml/ref/pg_dumpall.sgml
+++ b/doc/src/sgml/ref/pg_dumpall.sgml
@@ -430,6 +430,21 @@ PostgreSQL documentation
       </listitem>
      </varlistentry>
 
+     <varlistentry>
+      <term><option>--load-via-partition-root</></term>
+      <listitem>
+       <para>
+        When dumping a COPY or INSERT statement for a partitioned table,
+        target the root of the partitioning hierarchy which contains it rather
+        than the partition itself.  This may be useful when reloading data on
+        a server where rows do not always fall into the same partitions as
+        they did on the original server.  This could happen, for example, if
+        the partitioning column is of type text and the two system have
+        different definitions of the collation used to partition the data.
+       </para>
+      </listitem>
+     </varlistentry>
+
      <varlistentry>
       <term><option>--use-set-session-authorization</></term>
       <listitem>

diff --git a/src/bin/pg_dump/common.c b/src/bin/pg_dump/common.c
index 47191be86ad73cf2c89057abff8545c433716a7f..4b47951de1b73cd771b3a28edf622d0eadfd9a76 100644 (file)
--- a/src/bin/pg_dump/common.c
+++ b/src/bin/pg_dump/common.c
@@ -66,7 +66,7 @@ static int    numExtensions;
 static ExtensionMemberId *extmembers;
 static int numextmembers;
 
-static void flagInhTables(TableInfo *tbinfo, int numTables,
+static void flagInhTables(Archive *fout, TableInfo *tbinfo, int numTables,
              InhInfo *inhinfo, int numInherits);
 static void flagInhAttrs(DumpOptions *dopt, TableInfo *tblinfo, int numTables);
 static DumpableObject **buildIndexArray(void *objArray, int numObjs,
@@ -243,7 +243,7 @@ getSchemaData(Archive *fout, int *numTablesPtr)
    /* Link tables to parents, mark parents of target tables interesting */
    if (g_verbose)
        write_msg(NULL, "finding inheritance relationships\n");
-   flagInhTables(tblinfo, numTables, inhinfo, numInherits);
+   flagInhTables(fout, tblinfo, numTables, inhinfo, numInherits);
 
    if (g_verbose)
        write_msg(NULL, "reading column info for interesting tables\n");
@@ -294,8 +294,8 @@ getSchemaData(Archive *fout, int *numTablesPtr)
 }
 
 /* flagInhTables -
- *  Fill in parent link fields of every target table, and mark
- *  parents of target tables as interesting
+ *  Fill in parent link fields of tables for which we need that information,
+ *  and mark parents of target tables as interesting
  *
  * Note that only direct ancestors of targets are marked interesting.
  * This is sufficient; we don't much care whether they inherited their
@@ -304,34 +304,53 @@ getSchemaData(Archive *fout, int *numTablesPtr)
  * modifies tblinfo
  */
 static void
-flagInhTables(TableInfo *tblinfo, int numTables,
+flagInhTables(Archive *fout, TableInfo *tblinfo, int numTables,
              InhInfo *inhinfo, int numInherits)
 {
+   DumpOptions *dopt = fout->dopt;
    int         i,
                j;
-   int         numParents;
-   TableInfo **parents;
 
    for (i = 0; i < numTables; i++)
    {
+       bool        find_parents = true;
+       bool        mark_parents = true;
+
        /* Some kinds never have parents */
        if (tblinfo[i].relkind == RELKIND_SEQUENCE ||
            tblinfo[i].relkind == RELKIND_VIEW ||
            tblinfo[i].relkind == RELKIND_MATVIEW)
            continue;
 
-       /* Don't bother computing anything for non-target tables, either */
+       /*
+        * Normally, we don't bother computing anything for non-target tables,
+        * but if load-via-partition-root is specified, we gather information
+        * on every partition in the system so that getRootTableInfo can trace
+        * from any given to leaf partition all the way up to the root.  (We
+        * don't need to mark them as interesting for getTableAttrs, though.)
+        */
        if (!tblinfo[i].dobj.dump)
-           continue;
+       {
+           mark_parents = false;
 
-       /* Find all the immediate parent tables */
-       findParentsByOid(&tblinfo[i], inhinfo, numInherits);
+           if (!dopt->load_via_partition_root ||
+               !tblinfo[i].ispartition)
+               find_parents = false;
+       }
+
+       /* If needed, find all the immediate parent tables. */
+       if (find_parents)
+           findParentsByOid(&tblinfo[i], inhinfo, numInherits);
 
-       /* Mark the parents as interesting for getTableAttrs */
-       numParents = tblinfo[i].numParents;
-       parents = tblinfo[i].parents;
-       for (j = 0; j < numParents; j++)
-           parents[j]->interesting = true;
+       /* If needed, mark the parents as interesting for getTableAttrs. */
+       if (mark_parents)
+       {
+           int         numParents = tblinfo[i].numParents;
+           TableInfo **parents = tblinfo[i].parents;
+
+           for (j = 0; j < numParents; j++)
+               parents[j]->interesting = true;
+       }
    }
 }
 

diff --git a/src/bin/pg_dump/pg_backup.h b/src/bin/pg_dump/pg_backup.h
index 144068ac4922167a3eb2c89c92df26661ffd657d..ce3100f09d65a367994a2d3072eba9f9592ac18a 100644 (file)
--- a/src/bin/pg_dump/pg_backup.h
+++ b/src/bin/pg_dump/pg_backup.h
@@ -157,6 +157,7 @@ typedef struct _dumpOptions
    int         outputNoTablespaces;
    int         use_setsessauth;
    int         enable_row_security;
+   int         load_via_partition_root;
 
    /* default, if no "inclusion" switches appear, is to dump everything */
    bool        include_everything;

diff --git a/src/bin/pg_dump/pg_dump.c b/src/bin/pg_dump/pg_dump.c
index 2d8bb32dc07338953c3ae9e66319885b3b41360b..628bdea1fd498bcf961267763b6a2859c61c3f8e 100644 (file)
--- a/src/bin/pg_dump/pg_dump.c
+++ b/src/bin/pg_dump/pg_dump.c
@@ -269,6 +269,7 @@ static void appendReloptionsArrayAH(PQExpBuffer buffer, const char *reloptions,
                        const char *prefix, Archive *fout);
 static char *get_synchronized_snapshot(Archive *fout);
 static void setupDumpWorker(Archive *AHX);
+static TableInfo *getRootTableInfo(TableInfo *tbinfo);
 
 
 int
@@ -345,6 +346,7 @@ main(int argc, char **argv)
        {"lock-wait-timeout", required_argument, NULL, 2},
        {"no-tablespaces", no_argument, &dopt.outputNoTablespaces, 1},
        {"quote-all-identifiers", no_argument, &quote_all_identifiers, 1},
+       {"load-via-partition-root", no_argument, &dopt.load_via_partition_root, 1},
        {"role", required_argument, NULL, 3},
        {"section", required_argument, NULL, 5},
        {"serializable-deferrable", no_argument, &dopt.serializable_deferrable, 1},
@@ -959,6 +961,7 @@ help(const char *progname)
    printf(_("  --no-tablespaces             do not dump tablespace assignments\n"));
    printf(_("  --no-unlogged-table-data     do not dump unlogged table data\n"));
    printf(_("  --quote-all-identifiers      quote all identifiers, even if not key words\n"));
+   printf(_("  --load-via-partition-root    load partitions via the root table\n"));
    printf(_("  --section=SECTION            dump named section (pre-data, data, or post-data)\n"));
    printf(_("  --serializable-deferrable    wait until the dump can run without anomalies\n"));
    printf(_("  --snapshot=SNAPSHOT          use given snapshot for the dump\n"));
@@ -1902,8 +1905,32 @@ dumpTableData_insert(Archive *fout, void *dcontext)
            if (insertStmt == NULL)
            {
                insertStmt = createPQExpBuffer();
+
+               /*
+                * When load-via-partition-root is set, get the root table
+                * name for the partition table, so that we can reload data
+                * through the root table.
+                */
+               if (dopt->load_via_partition_root && tbinfo->ispartition)
+               {
+                   TableInfo  *parentTbinfo;
+
+                   parentTbinfo = getRootTableInfo(tbinfo);
+
+                   /*
+                    * When we loading data through the root, we will qualify
+                    * the table name. This is needed because earlier
+                    * search_path will be set for the partition table.
+                    */
+                   classname = (char *) fmtQualifiedId(fout->remoteVersion,
+                                                       parentTbinfo->dobj.namespace->dobj.name,
+                                                       parentTbinfo->dobj.name);
+               }
+               else
+                   classname = fmtId(tbinfo->dobj.name);
+
                appendPQExpBuffer(insertStmt, "INSERT INTO %s ",
-                                 fmtId(classname));
+                                 classname);
 
                /* corner case for zero-column table */
                if (nfields == 0)
@@ -2025,6 +2052,27 @@ dumpTableData_insert(Archive *fout, void *dcontext)
    return 1;
 }
 
+/*
+ * getRootTableInfo:
+ *     get the root TableInfo for the given partition table.
+ */
+static TableInfo *
+getRootTableInfo(TableInfo *tbinfo)
+{
+   TableInfo  *parentTbinfo;
+
+   Assert(tbinfo->ispartition);
+   Assert(tbinfo->numParents == 1);
+
+   parentTbinfo = tbinfo->parents[0];
+   while (parentTbinfo->ispartition)
+   {
+       Assert(parentTbinfo->numParents == 1);
+       parentTbinfo = parentTbinfo->parents[0];
+   }
+
+   return parentTbinfo;
+}
 
 /*
  * dumpTableData -
@@ -2041,14 +2089,38 @@ dumpTableData(Archive *fout, TableDataInfo *tdinfo)
    PQExpBuffer clistBuf = createPQExpBuffer();
    DataDumperPtr dumpFn;
    char       *copyStmt;
+   const char *copyFrom;
 
    if (!dopt->dump_inserts)
    {
        /* Dump/restore using COPY */
        dumpFn = dumpTableData_copy;
+
+       /*
+        * When load-via-partition-root is set, get the root table name for
+        * the partition table, so that we can reload data through the root
+        * table.
+        */
+       if (dopt->load_via_partition_root && tbinfo->ispartition)
+       {
+           TableInfo  *parentTbinfo;
+
+           parentTbinfo = getRootTableInfo(tbinfo);
+
+           /*
+            * When we load data through the root, we will qualify the table
+            * name, because search_path is set for the partition.
+            */
+           copyFrom = fmtQualifiedId(fout->remoteVersion,
+                                     parentTbinfo->dobj.namespace->dobj.name,
+                                     parentTbinfo->dobj.name);
+       }
+       else
+           copyFrom = fmtId(tbinfo->dobj.name);
+
        /* must use 2 steps here 'cause fmtId is nonreentrant */
        appendPQExpBuffer(copyBuf, "COPY %s ",
-                         fmtId(tbinfo->dobj.name));
+                         copyFrom);
        appendPQExpBuffer(copyBuf, "%s %sFROM stdin;\n",
                          fmtCopyColumnList(tbinfo, clistBuf),
                          (tdinfo->oids && tbinfo->hasoids) ? "WITH OIDS " : "");

diff --git a/src/bin/pg_dump/pg_dumpall.c b/src/bin/pg_dump/pg_dumpall.c
index b14bb8e963fcac52087d1c8d6a805e593d329239..c0a0346cd9c9bb39f2a3702a4d58fa0af1334fec 100644 (file)
--- a/src/bin/pg_dump/pg_dumpall.c
+++ b/src/bin/pg_dump/pg_dumpall.c
@@ -80,6 +80,7 @@ static int    no_subscriptions = 0;
 static int no_unlogged_table_data = 0;
 static int no_role_passwords = 0;
 static int server_version;
+static int load_via_partition_root = 0;
 
 static char role_catalog[10];
 #define PG_AUTHID "pg_authid"
@@ -128,6 +129,7 @@ main(int argc, char *argv[])
        {"lock-wait-timeout", required_argument, NULL, 2},
        {"no-tablespaces", no_argument, &no_tablespaces, 1},
        {"quote-all-identifiers", no_argument, &quote_all_identifiers, 1},
+       {"load-via-partition-root", no_argument, &load_via_partition_root, 1},
        {"role", required_argument, NULL, 3},
        {"use-set-session-authorization", no_argument, &use_setsessauth, 1},
        {"no-publications", no_argument, &no_publications, 1},
@@ -385,6 +387,8 @@ main(int argc, char *argv[])
        appendPQExpBufferStr(pgdumpopts, " --no-tablespaces");
    if (quote_all_identifiers)
        appendPQExpBufferStr(pgdumpopts, " --quote-all-identifiers");
+   if (load_via_partition_root)
+       appendPQExpBufferStr(pgdumpopts, " --load-via-partition-root");
    if (use_setsessauth)
        appendPQExpBufferStr(pgdumpopts, " --use-set-session-authorization");
    if (no_publications)
@@ -606,6 +610,7 @@ help(void)
    printf(_("  --no-tablespaces             do not dump tablespace assignments\n"));
    printf(_("  --no-unlogged-table-data     do not dump unlogged table data\n"));
    printf(_("  --quote-all-identifiers      quote all identifiers, even if not key words\n"));
+   printf(_("  --load-via-partition-root    load partitions via the root table\n"));
    printf(_("  --use-set-session-authorization\n"
             "                               use SET SESSION AUTHORIZATION commands instead of\n"
             "                               ALTER OWNER commands to set ownership\n"));