Make native Rust planner the default, PL/pgSQL opt-in

The native planner is 10-13x faster with O(1) scaling at the 1M+ row
benchmark. It now runs by default without any GUC setting.

To fall back to PL/pgSQL:
  SET sql_saga.temporal_merge.use_plpgsql_planner = true;

Swaps primary/alternate expected files so native output is the primary
expected result. Removes orphan expected files that didn't match any test.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

Author: jhf

expected/060_temporal_merge_basic.out

@@ -281,23 +281,21 @@ CALL sql_saga.temporal_merge(
     primary_identity_columns => '{id}'::text[]
 );
 ERROR:  Source table "source_boundary" must have either the range column "valid_range" or the component column "<NULL>".
-CONTEXT:  PL/pgSQL function sql_saga.temporal_merge_plan(regclass,regclass,sql_saga.temporal_merge_mode,name,text[],name,name,sql_saga.temporal_merge_delete_mode,jsonb,text[],boolean,boolean) line 294 at RAISE
-SQL statement "INSERT INTO temporal_merge_plan
-        SELECT * FROM sql_saga.temporal_merge_plan(
-            target_table => temporal_merge.target_table,
-            source_table => temporal_merge.source_table,
-            mode => temporal_merge.mode,
-            era_name => temporal_merge.era_name,
-            identity_columns => v_identity_cols_discovered,
-            row_id_column => temporal_merge.row_id_column,
-            founding_id_column => temporal_merge.founding_id_column,
-            delete_mode => temporal_merge.delete_mode,
-            lookup_keys => v_natural_identity_keys_discovered,
-            ephemeral_columns => temporal_merge.ephemeral_columns,
-            p_log_trace => v_log_trace,
-            p_log_sql => v_log_sql
-        )"
-PL/pgSQL function sql_saga.temporal_merge(regclass,regclass,text[],sql_saga.temporal_merge_mode,name,name,name,boolean,text[],sql_saga.temporal_merge_delete_mode,boolean,name,name,name,name,text[],boolean) line 207 at SQL statement
+CONTEXT:  SQL statement "SELECT sql_saga.temporal_merge_plan_native(
+                target_table => temporal_merge.target_table::oid,
+                source_table => temporal_merge.source_table::oid,
+                mode => temporal_merge.mode::text,
+                era_name => temporal_merge.era_name::text,
+                identity_columns => v_identity_cols_discovered,
+                row_id_column => temporal_merge.row_id_column::text,
+                founding_id_column => temporal_merge.founding_id_column::text,
+                delete_mode => temporal_merge.delete_mode::text,
+                lookup_keys => v_natural_identity_keys_discovered,
+                ephemeral_columns => temporal_merge.ephemeral_columns,
+                p_log_trace => v_log_trace,
+                p_log_sql => v_log_sql
+            )"
+PL/pgSQL function sql_saga.temporal_merge(regclass,regclass,text[],sql_saga.temporal_merge_mode,name,name,name,boolean,text[],sql_saga.temporal_merge_delete_mode,boolean,name,name,name,name,text[],boolean) line 192 at PERFORM
 ROLLBACK TO SAVEPOINT expect_error;
 \echo '--- Workaround: Use a view to compute the range from boundary columns ---'
 --- Workaround: Use a view to compute the range from boundary columns ---

expected/066_temporal_merge_range_only.out

@@ -281,21 +281,23 @@ CALL sql_saga.temporal_merge(
     primary_identity_columns => '{id}'::text[]
 );
 ERROR:  Source table "source_boundary" must have either the range column "valid_range" or the component column "<NULL>".
-CONTEXT:  SQL statement "SELECT sql_saga.temporal_merge_plan_native(
-                target_table => temporal_merge.target_table::oid,
-                source_table => temporal_merge.source_table::oid,
-                mode => temporal_merge.mode::text,
-                era_name => temporal_merge.era_name::text,
-                identity_columns => v_identity_cols_discovered,
-                row_id_column => temporal_merge.row_id_column::text,
-                founding_id_column => temporal_merge.founding_id_column::text,
-                delete_mode => temporal_merge.delete_mode::text,
-                lookup_keys => v_natural_identity_keys_discovered,
-                ephemeral_columns => temporal_merge.ephemeral_columns,
-                p_log_trace => v_log_trace,
-                p_log_sql => v_log_sql
-            )"
-PL/pgSQL function sql_saga.temporal_merge(regclass,regclass,text[],sql_saga.temporal_merge_mode,name,name,name,boolean,text[],sql_saga.temporal_merge_delete_mode,boolean,name,name,name,name,text[],boolean) line 192 at PERFORM
+CONTEXT:  PL/pgSQL function sql_saga.temporal_merge_plan(regclass,regclass,sql_saga.temporal_merge_mode,name,text[],name,name,sql_saga.temporal_merge_delete_mode,jsonb,text[],boolean,boolean) line 294 at RAISE
+SQL statement "INSERT INTO temporal_merge_plan
+        SELECT * FROM sql_saga.temporal_merge_plan(
+            target_table => temporal_merge.target_table,
+            source_table => temporal_merge.source_table,
+            mode => temporal_merge.mode,
+            era_name => temporal_merge.era_name,
+            identity_columns => v_identity_cols_discovered,
+            row_id_column => temporal_merge.row_id_column,
+            founding_id_column => temporal_merge.founding_id_column,
+            delete_mode => temporal_merge.delete_mode,
+            lookup_keys => v_natural_identity_keys_discovered,
+            ephemeral_columns => temporal_merge.ephemeral_columns,
+            p_log_trace => v_log_trace,
+            p_log_sql => v_log_sql
+        )"
+PL/pgSQL function sql_saga.temporal_merge(regclass,regclass,text[],sql_saga.temporal_merge_mode,name,name,name,boolean,text[],sql_saga.temporal_merge_delete_mode,boolean,name,name,name,name,text[],boolean) line 207 at SQL statement
 ROLLBACK TO SAVEPOINT expect_error;
 \echo '--- Workaround: Use a view to compute the range from boundary columns ---'
 --- Workaround: Use a view to compute the range from boundary columns ---

expected/066_temporal_merge_range_only_1.out

@@ -248,7 +248,7 @@ EXCEPTION WHEN others THEN
     RAISE NOTICE 'Caught expected error for non-existent row_id_column: %', SQLERRM;
 END;
 $$;
-NOTICE:  Caught expected error for non-existent row_id_column: row_id_column "non_existent_row_id" does not exist in source table tm_bad_cols_sources
+NOTICE:  Caught expected error for non-existent row_id_column: row_id_column "non_existent_row_id" does not exist in source table tm_bad_cols_source
 -- Test with non-existent founding_id_column
 DO $$
 BEGIN
@@ -264,7 +264,7 @@ EXCEPTION WHEN others THEN
     RAISE NOTICE 'Caught expected error for non-existent founding_id_column: %', SQLERRM;
 END;
 $$;
-NOTICE:  Caught expected error for non-existent founding_id_column: founding_id_column "non_existent_founding_id" does not exist in source table tm_bad_cols_sources
+NOTICE:  Caught expected error for non-existent founding_id_column: founding_id_column "non_existent_founding_id" does not exist in source table tm_bad_cols_source
 ROLLBACK TO SAVEPOINT scenario_10;
 SAVEPOINT scenario_11;
 -- Scenario 11: Test using a non-default row_id_column name.
@@ -362,7 +362,7 @@ EXCEPTION WHEN others THEN
     RAISE NOTICE 'Caught expected error for missing default row_id column: %', SQLERRM;
 END;
 $$;
-NOTICE:  Caught expected error for missing default row_id column: row_id_column "row_id" does not exist in source table tm_no_rowid_sourcess
+NOTICE:  Caught expected error for missing default row_id column: row_id_column "row_id" does not exist in source table tm_no_rowid_sources
 ROLLBACK TO SAVEPOINT scenario_12;
 SAVEPOINT scenario_13;
 -- Scenario 13: Test `temporal_merge` with non-standard column and era names.

expected/067_temporal_merge_parameters.out

@@ -248,7 +248,7 @@ EXCEPTION WHEN others THEN
     RAISE NOTICE 'Caught expected error for non-existent row_id_column: %', SQLERRM;
 END;
 $$;
-NOTICE:  Caught expected error for non-existent row_id_column: row_id_column "non_existent_row_id" does not exist in source table tm_bad_cols_source
+NOTICE:  Caught expected error for non-existent row_id_column: row_id_column "non_existent_row_id" does not exist in source table tm_bad_cols_sources
 -- Test with non-existent founding_id_column
 DO $$
 BEGIN
@@ -264,7 +264,7 @@ EXCEPTION WHEN others THEN
     RAISE NOTICE 'Caught expected error for non-existent founding_id_column: %', SQLERRM;
 END;
 $$;
-NOTICE:  Caught expected error for non-existent founding_id_column: founding_id_column "non_existent_founding_id" does not exist in source table tm_bad_cols_source
+NOTICE:  Caught expected error for non-existent founding_id_column: founding_id_column "non_existent_founding_id" does not exist in source table tm_bad_cols_sources
 ROLLBACK TO SAVEPOINT scenario_10;
 SAVEPOINT scenario_11;
 -- Scenario 11: Test using a non-default row_id_column name.
@@ -362,7 +362,7 @@ EXCEPTION WHEN others THEN
     RAISE NOTICE 'Caught expected error for missing default row_id column: %', SQLERRM;
 END;
 $$;
-NOTICE:  Caught expected error for missing default row_id column: row_id_column "row_id" does not exist in source table tm_no_rowid_sources
+NOTICE:  Caught expected error for missing default row_id column: row_id_column "row_id" does not exist in source table tm_no_rowid_sourcess
 ROLLBACK TO SAVEPOINT scenario_12;
 SAVEPOINT scenario_13;
 -- Scenario 13: Test `temporal_merge` with non-standard column and era names.

expected/067_temporal_merge_parameters_1.out

@@ -91,23 +91,21 @@ CALL sql_saga.temporal_merge(
     natural_identity_columns => ARRAY['org_nr_typo']
 );
 ERROR:  lookup_column org_nr_typo does not exist in target table repro.units
-CONTEXT:  PL/pgSQL function sql_saga.temporal_merge_plan(regclass,regclass,sql_saga.temporal_merge_mode,name,text[],name,name,sql_saga.temporal_merge_delete_mode,jsonb,text[],boolean,boolean) line 493 at RAISE
-SQL statement "INSERT INTO temporal_merge_plan
-        SELECT * FROM sql_saga.temporal_merge_plan(
-            target_table => temporal_merge.target_table,
-            source_table => temporal_merge.source_table,
-            mode => temporal_merge.mode,
-            era_name => temporal_merge.era_name,
-            identity_columns => v_identity_cols_discovered,
-            row_id_column => temporal_merge.row_id_column,
-            founding_id_column => temporal_merge.founding_id_column,
-            delete_mode => temporal_merge.delete_mode,
-            lookup_keys => v_natural_identity_keys_discovered,
-            ephemeral_columns => temporal_merge.ephemeral_columns,
-            p_log_trace => v_log_trace,
-            p_log_sql => v_log_sql
-        )"
-PL/pgSQL function sql_saga.temporal_merge(regclass,regclass,text[],sql_saga.temporal_merge_mode,name,name,name,boolean,text[],sql_saga.temporal_merge_delete_mode,boolean,name,name,name,name,text[],boolean) line 207 at SQL statement
+CONTEXT:  SQL statement "SELECT sql_saga.temporal_merge_plan_native(
+                target_table => temporal_merge.target_table::oid,
+                source_table => temporal_merge.source_table::oid,
+                mode => temporal_merge.mode::text,
+                era_name => temporal_merge.era_name::text,
+                identity_columns => v_identity_cols_discovered,
+                row_id_column => temporal_merge.row_id_column::text,
+                founding_id_column => temporal_merge.founding_id_column::text,
+                delete_mode => temporal_merge.delete_mode::text,
+                lookup_keys => v_natural_identity_keys_discovered,
+                ephemeral_columns => temporal_merge.ephemeral_columns,
+                p_log_trace => v_log_trace,
+                p_log_sql => v_log_sql
+            )"
+PL/pgSQL function sql_saga.temporal_merge(regclass,regclass,text[],sql_saga.temporal_merge_mode,name,name,name,boolean,text[],sql_saga.temporal_merge_delete_mode,boolean,name,name,name,name,text[],boolean) line 192 at PERFORM
 ROLLBACK TO SAVEPOINT expect_error;
 \echo '--- Scenario 3: FAIL - natural_identity_column missing from target ---'
 --- Scenario 3: FAIL - natural_identity_column missing from target ---
@@ -120,24 +118,22 @@ CALL sql_saga.temporal_merge(
     primary_identity_columns => ARRAY['id'],
     natural_identity_columns => ARRAY['org_nr_typo']
 );
-ERROR:  Source table "source_with_typo" must have a "valid_range", "valid_until", or "<NULL>" column.
-CONTEXT:  PL/pgSQL function sql_saga.temporal_merge_plan(regclass,regclass,sql_saga.temporal_merge_mode,name,text[],name,name,sql_saga.temporal_merge_delete_mode,jsonb,text[],boolean,boolean) line 322 at RAISE
-SQL statement "INSERT INTO temporal_merge_plan
-        SELECT * FROM sql_saga.temporal_merge_plan(
-            target_table => temporal_merge.target_table,
-            source_table => temporal_merge.source_table,
-            mode => temporal_merge.mode,
-            era_name => temporal_merge.era_name,
-            identity_columns => v_identity_cols_discovered,
-            row_id_column => temporal_merge.row_id_column,
-            founding_id_column => temporal_merge.founding_id_column,
-            delete_mode => temporal_merge.delete_mode,
-            lookup_keys => v_natural_identity_keys_discovered,
-            ephemeral_columns => temporal_merge.ephemeral_columns,
-            p_log_trace => v_log_trace,
-            p_log_sql => v_log_sql
-        )"
-PL/pgSQL function sql_saga.temporal_merge(regclass,regclass,text[],sql_saga.temporal_merge_mode,name,name,name,boolean,text[],sql_saga.temporal_merge_delete_mode,boolean,name,name,name,name,text[],boolean) line 207 at SQL statement
+ERROR:  lookup_column org_nr_typo does not exist in target table repro.units
+CONTEXT:  SQL statement "SELECT sql_saga.temporal_merge_plan_native(
+                target_table => temporal_merge.target_table::oid,
+                source_table => temporal_merge.source_table::oid,
+                mode => temporal_merge.mode::text,
+                era_name => temporal_merge.era_name::text,
+                identity_columns => v_identity_cols_discovered,
+                row_id_column => temporal_merge.row_id_column::text,
+                founding_id_column => temporal_merge.founding_id_column::text,
+                delete_mode => temporal_merge.delete_mode::text,
+                lookup_keys => v_natural_identity_keys_discovered,
+                ephemeral_columns => temporal_merge.ephemeral_columns,
+                p_log_trace => v_log_trace,
+                p_log_sql => v_log_sql
+            )"
+PL/pgSQL function sql_saga.temporal_merge(regclass,regclass,text[],sql_saga.temporal_merge_mode,name,name,name,boolean,text[],sql_saga.temporal_merge_delete_mode,boolean,name,name,name,name,text[],boolean) line 192 at PERFORM
 ROLLBACK TO SAVEPOINT expect_error;
 \echo '--- Scenario 4: FAIL - identity_column missing from target ---'
 --- Scenario 4: FAIL - identity_column missing from target ---
@@ -150,24 +146,22 @@ CALL sql_saga.temporal_merge(
     primary_identity_columns => ARRAY['id_typo'],
     natural_identity_columns => ARRAY['org_nr']
 );
-ERROR:  Source table "source_with_id" must have a "valid_range", "valid_until", or "<NULL>" column.
-CONTEXT:  PL/pgSQL function sql_saga.temporal_merge_plan(regclass,regclass,sql_saga.temporal_merge_mode,name,text[],name,name,sql_saga.temporal_merge_delete_mode,jsonb,text[],boolean,boolean) line 322 at RAISE
-SQL statement "INSERT INTO temporal_merge_plan
-        SELECT * FROM sql_saga.temporal_merge_plan(
-            target_table => temporal_merge.target_table,
-            source_table => temporal_merge.source_table,
-            mode => temporal_merge.mode,
-            era_name => temporal_merge.era_name,
-            identity_columns => v_identity_cols_discovered,
-            row_id_column => temporal_merge.row_id_column,
-            founding_id_column => temporal_merge.founding_id_column,
-            delete_mode => temporal_merge.delete_mode,
-            lookup_keys => v_natural_identity_keys_discovered,
-            ephemeral_columns => temporal_merge.ephemeral_columns,
-            p_log_trace => v_log_trace,
-            p_log_sql => v_log_sql
-        )"
-PL/pgSQL function sql_saga.temporal_merge(regclass,regclass,text[],sql_saga.temporal_merge_mode,name,name,name,boolean,text[],sql_saga.temporal_merge_delete_mode,boolean,name,name,name,name,text[],boolean) line 207 at SQL statement
+ERROR:  identity_column id_typo does not exist in target table repro.units
+CONTEXT:  SQL statement "SELECT sql_saga.temporal_merge_plan_native(
+                target_table => temporal_merge.target_table::oid,
+                source_table => temporal_merge.source_table::oid,
+                mode => temporal_merge.mode::text,
+                era_name => temporal_merge.era_name::text,
+                identity_columns => v_identity_cols_discovered,
+                row_id_column => temporal_merge.row_id_column::text,
+                founding_id_column => temporal_merge.founding_id_column::text,
+                delete_mode => temporal_merge.delete_mode::text,
+                lookup_keys => v_natural_identity_keys_discovered,
+                ephemeral_columns => temporal_merge.ephemeral_columns,
+                p_log_trace => v_log_trace,
+                p_log_sql => v_log_sql
+            )"
+PL/pgSQL function sql_saga.temporal_merge(regclass,regclass,text[],sql_saga.temporal_merge_mode,name,name,name,boolean,text[],sql_saga.temporal_merge_delete_mode,boolean,name,name,name,name,text[],boolean) line 192 at PERFORM
 ROLLBACK TO SAVEPOINT expect_error;
 \echo '--- Scenario 5: Happy path (ID back-filling) ---'
 --- Scenario 5: Happy path (ID back-filling) ---