Merge pull request #365 from CartoDB/table-syncer-notmps

Sync tables without using temporary hash tables

NEWS.md

@@ -1,3 +1,6 @@
+x.y.z (YYYY-MM-DD)
+* Avoid temporary tables creation in CDB_SyncTable (#366)
+
 0.28.0 (2019-07-01)
 * New function CDB_SyncTable (#355)
 

scripts-available/CDB_CartodbfyTable.sql

@@ -1071,7 +1071,7 @@ BEGIN
   -- by selecting their names into an array and
   -- joining the array with a comma
   SELECT
-    ',' || array_to_string(array_agg(Format('%I',a.attname)),',') AS column_name_sql,
+    ',' || array_to_string(array_agg(Format('%I',a.attname) ORDER BY a.attnum),',') AS column_name_sql,
     Count(*) AS count
   INTO rec
   FROM pg_class c

scripts-available/CDB_SyncTable.sql

@@ -21,7 +21,8 @@ AS $$
           LEFT JOIN pg_catalog.pg_namespace n ON n.oid = c.relnamespace
           WHERE c.oid = src_table::oid
             AND pg_catalog.pg_table_is_visible(c.oid)
-      );
+      )
+  ORDER BY a.attnum;
 $$ LANGUAGE sql STABLE PARALLEL UNSAFE;
 
 
@@ -67,6 +68,21 @@ AS $$
   SELECT format('%s_%s_%s', prefix, txid_current(), (random()*1000000)::int)::NAME;
 $$ LANGUAGE sql VOLATILE PARALLEL UNSAFE;
 
+/*
+    Given a table name and an array of column names,
+    return array of column names qualified with the table name and quoted when necessary
+    tablename and colnames should be properly quoted, and for this reason the type NAME is not
+    used for them (with quotes they could exceed the maximum identifier length)
+
+    Example of usage:
+
+       SELECT @extschema@.__CDB_QualifyColumns('t', ARRAY['a','"b-1"']); --> ARRAY['t.a','t."b-1"']
+
+*/
+CREATE OR REPLACE FUNCTION @extschema@.__CDB_QualifyColumns(tablename NAME, colnames NAME[]) RETURNS TEXT[] AS
+$$
+    SELECT array_agg(tablename || '.' || _colname) from unnest(colnames) _colname;
+$$ LANGUAGE sql IMMUTABLE PARALLEL SAFE;
 
 /*
    A Table Syncer
@@ -88,10 +104,8 @@ DECLARE
   fq_dest_table TEXT;
 
   colnames TEXT[];
-  quoted_colnames TEXT;
+  dst_colnames TEXT;
-
+  src_colnames TEXT;
-  src_hash_table_name NAME;
-  dst_hash_table_name NAME;
 
   update_set_clause TEXT;
 
@@ -101,8 +115,8 @@ DECLARE
   t timestamptz;
 BEGIN
   -- If the destination table does not exist, just copy the source table
-  fq_dest_table := format('%I.%I', dst_schema, dst_table);
+  fq_dest_table := format('%s.%I', dst_schema, dst_table);
-  EXECUTE format('CREATE TABLE IF NOT EXISTS %s as TABLE %I', fq_dest_table, src_table);
+  EXECUTE format('CREATE TABLE IF NOT EXISTS %s as TABLE %s', fq_dest_table, src_table);
   GET DIAGNOSTICS num_rows = ROW_COUNT;
   IF num_rows > 0 THEN
     RAISE NOTICE 'INSERTED % row(s)', num_rows;
@@ -113,35 +127,12 @@ BEGIN
 
   -- Get the list of columns from the source table, excluding skip_cols
   SELECT ARRAY(SELECT quote_ident(c) FROM @extschema@._CDB_GetColumns(src_table) as c EXCEPT SELECT unnest(skip_cols)) INTO colnames;
-  quoted_colnames := array_to_string(colnames, ',');
-
-  src_hash_table_name := @extschema@.__CDB_GenerateUniqueName('src_sync');
-  dst_hash_table_name := @extschema@.__CDB_GenerateUniqueName('dst_sync');
-
-  EXECUTE format('CREATE TEMP TABLE %I(cartodb_id BIGINT, hash TEXT) ON COMMIT DROP', src_hash_table_name);
-  EXECUTE format('CREATE TEMP TABLE %I(cartodb_id BIGINT, hash TEXT) ON COMMIT DROP', dst_hash_table_name);
-
-  -- Compute hash tables for src_table and dst_table h[cartodb_id] = hash(row)
-  -- It'll take the form of a temp table with an index (easy to run set operations)
-  t := clock_timestamp();
-  EXECUTE format('INSERT INTO %I SELECT cartodb_id, md5(ROW(%s)::text) hash FROM %I', src_hash_table_name, quoted_colnames, src_table);
-  EXECUTE format('INSERT INTO %I SELECT cartodb_id, md5(ROW(%s)::text) hash FROM %s', dst_hash_table_name, quoted_colnames, fq_dest_table);
-  RAISE DEBUG 'Populate hash tables time (s): %', clock_timestamp() - t;
-
-  -- Create indexes
-  -- We use hash indexes as they are fit for id comparison.
-  t := clock_timestamp();
-  EXECUTE format('CREATE INDEX ON %I USING HASH (cartodb_id)', src_hash_table_name);
-  EXECUTE format('CREATE INDEX ON %I USING HASH (cartodb_id)', dst_hash_table_name);
-  RAISE DEBUG 'Index creation on hash tables time (s): %', clock_timestamp() - t;
 
   -- Deal with deleted rows: ids in dest but not in source
   t := clock_timestamp();
   EXECUTE format(
-    'DELETE FROM %s WHERE cartodb_id IN (SELECT cartodb_id FROM %I EXCEPT SELECT cartodb_id FROM %I)',
+    'DELETE FROM %1$s _dst WHERE NOT EXISTS (SELECT * FROM %2$s _src WHERE _src.cartodb_id=_dst.cartodb_id)',
-    fq_dest_table,
+    fq_dest_table, src_table);
-    dst_hash_table_name,
-    src_hash_table_name);
   GET DIAGNOSTICS num_rows = ROW_COUNT;
   RAISE NOTICE 'DELETED % row(s)', num_rows;
   RAISE DEBUG 'DELETE time (s): %', clock_timestamp() - t;
@@ -149,29 +140,26 @@ BEGIN
   -- Deal with inserted rows: ids in source but not in dest
   t := clock_timestamp();
   EXECUTE format('
-      INSERT INTO %1$s (cartodb_id,%2$s)
+      INSERT INTO %1$s(cartodb_id, %2$s)
-      SELECT h.cartodb_id,%2$s FROM (SELECT cartodb_id FROM %3$I EXCEPT SELECT cartodb_id FROM %4$I) h
+      SELECT cartodb_id, %2$s FROM %3$s _src WHERE NOT EXISTS (SELECT * FROM %1$s _dst WHERE _src.cartodb_id=_dst.cartodb_id)
-      LEFT JOIN %5$I s ON s.cartodb_id = h.cartodb_id;
+  ', fq_dest_table, array_to_string(colnames, ','), src_table);
-  ', fq_dest_table, quoted_colnames, src_hash_table_name, dst_hash_table_name, src_table);
   GET DIAGNOSTICS num_rows = ROW_COUNT;
   RAISE NOTICE 'INSERTED % row(s)', num_rows;
   RAISE DEBUG 'INSERT time (s): %', clock_timestamp() - t;
 
   -- Deal with modified rows: ids in source and dest but different hashes
   t := clock_timestamp();
-  update_set_clause := @extschema@.__CDB_GetUpdateSetClause(colnames, 'changed');
+  update_set_clause :=  @extschema@.__CDB_GetUpdateSetClause(colnames, '_changed');
+  dst_colnames := array_to_string(@extschema@.__CDB_QualifyColumns('_dst', colnames), ',');
+  src_colnames := array_to_string(@extschema@.__CDB_QualifyColumns('_src', colnames), ',');
   EXECUTE format('
-    UPDATE %1$s dst SET %2$s
+      UPDATE %1$s _update SET %2$s
-    FROM (
+      FROM (
-      SELECT *
+        SELECT _src.* FROM %3$s _src JOIN %1$s _dst ON (_dst.cartodb_id = _src.cartodb_id)
-      FROM %3$s src
+        WHERE  md5(ROW(%4$s)::text) <> md5(ROW(%5$s)::text)
-      WHERE cartodb_id IN
+      ) _changed
-        (SELECT sh.cartodb_id FROM %4$I sh
+      WHERE _update.cartodb_id = _changed.cartodb_id;
-         LEFT JOIN %5$I dh ON sh.cartodb_id = dh.cartodb_id
+  ', fq_dest_table, update_set_clause, src_table, dst_colnames, src_colnames);
-         WHERE sh.hash <> dh.hash)
-    ) changed
-    WHERE dst.cartodb_id = changed.cartodb_id;
-  ', fq_dest_table, update_set_clause, src_table, src_hash_table_name, dst_hash_table_name);
   GET DIAGNOSTICS num_rows = ROW_COUNT;
   RAISE NOTICE 'MODIFIED % row(s)', num_rows;
   RAISE DEBUG 'UPDATE time (s): %', clock_timestamp() - t;

test/CDB_SyncTableTest.sql

@@ -50,9 +50,45 @@ UPDATE test_sync_dest SET the_geom = cartodb.CDB_LatLng(lat, lon); -- A "gecodin
 \set QUIET off
 SET client_min_messages TO notice;
 SELECT cartodb.CDB_SyncTable('test_sync_source', 'public', 'test_sync_dest', '{the_geom, the_geom_webmercator}');
-SELECT * FROM test_sync_source;
+SELECT * FROM test_sync_source ORDER BY cartodb_id;
-SELECT * FROM test_sync_dest;
+SELECT * FROM test_sync_dest ORDER BY cartodb_id;
 
+\echo 'It will work with schemas that need quoting'
+\set QUIET on
+SET client_min_messages TO error;
+CREATE SCHEMA "sch-ema";
+CREATE TABLE "test_sync_source2" AS SELECT * FROM test_sync_source;
+\set QUIET off
+SELECT cartodb.CDB_SyncTable('test_sync_source2', 'sch-ema', 'test_sync_dest');
+INSERT INTO test_sync_source2(cartodb_id, lat, lon, name) VALUES (6, 6.0, 6.0, 'papaya');
+DELETE FROM test_sync_source2 WHERE cartodb_id = 4;
+UPDATE test_sync_source2 SET lat = 2.5 WHERE cartodb_id = 2;
+SET client_min_messages TO notice;
+SELECT cartodb.CDB_SyncTable('test_sync_source2', 'sch-ema', 'test_sync_dest');
+
+\echo 'It will work with table names that need quoting'
+\set QUIET on
+SET client_min_messages TO error;
+CREATE TABLE "test-sync-source" AS SELECT * FROM test_sync_source;
+\set QUIET off
+SELECT cartodb.CDB_SyncTable('test-sync-source', 'public', 'test-sync-dest');
+INSERT INTO "test-sync-source"(cartodb_id, lat, lon, name) VALUES (6, 6.0, 6.0, 'papaya');
+DELETE FROM "test-sync-source" WHERE cartodb_id = 4;
+UPDATE "test-sync-source" SET lat = 2.5 WHERE cartodb_id = 2;
+SET client_min_messages TO notice;
+SELECT cartodb.CDB_SyncTable('test-sync-source', 'public', 'test-sync-dest');
+
+\echo 'It will work with column names that need quoting'
+\set QUIET on
+SET client_min_messages TO error;
+ALTER TABLE test_sync_source ADD COLUMN "a-column" int;
+\set QUIET off
+SELECT cartodb.CDB_SyncTable('test_sync_source', 'public', 'test_sync_dest2');
+INSERT INTO test_sync_source(cartodb_id, lat, lon, name) VALUES (6, 6.0, 6.0, 'papaya');
+DELETE FROM test_sync_source WHERE cartodb_id = 4;
+UPDATE test_sync_source SET lat = 2.5 WHERE cartodb_id = 2;
+SET client_min_messages TO notice;
+SELECT cartodb.CDB_SyncTable('test_sync_source', 'public', 'test_sync_dest2');
 
 -- Cleanup
 ROLLBACK;

test/CDB_SyncTableTest_expect

@@ -52,10 +52,43 @@ NOTICE:  MODIFIED 0 row(s)
 
 1|||1|1|foo
 2|||2|2|bar
-5|||5|5|sandia
 4|||4|4|cantaloupe
+5|||5|5|sandia
 1|0101000020E6100000000000000000F03F000000000000F03F|0101000020110F0000DB0B4ADA772DFB402B432E49D22DFB40|1|1|foo
 2|0101000020E610000000000000000000400000000000000040|0101000020110F00003C0C4ADA772D0B4177F404ABE12E0B41|2|2|bar
-5|0101000020E610000000000000000014400000000000001440|0101000020110F000099476EE86AFC20413E7EB983F2012141|5|5|sandia
 4|0101000020E610000000000000000010400000000000001040|0101000020110F00003C0C4ADA772D1B4160AB497020331B41|4|4|cantaloupe
+5|0101000020E610000000000000000014400000000000001440|0101000020110F000099476EE86AFC20413E7EB983F2012141|5|5|sandia
+It will work with schemas that need quoting
+
+INSERT 0 1
+DELETE 1
+UPDATE 1
+SET
+NOTICE:  relation "test_sync_dest" already exists, skipping
+NOTICE:  DELETED 1 row(s)
+NOTICE:  INSERTED 1 row(s)
+NOTICE:  MODIFIED 1 row(s)
+
+It will work with table names that need quoting
+
+INSERT 0 1
+DELETE 1
+UPDATE 1
+SET
+NOTICE:  relation "test-sync-dest" already exists, skipping
+NOTICE:  DELETED 1 row(s)
+NOTICE:  INSERTED 1 row(s)
+NOTICE:  MODIFIED 1 row(s)
+
+It will work with column names that need quoting
+
+INSERT 0 1
+DELETE 1
+UPDATE 1
+SET
+NOTICE:  relation "test_sync_dest2" already exists, skipping
+NOTICE:  DELETED 1 row(s)
+NOTICE:  INSERTED 1 row(s)
+NOTICE:  MODIFIED 1 row(s)
+
 ROLLBACK