Feature - Current version history (#71)

* Adds a new feature to the extension that enables the current versions of records to also be stored in the history table
* adding some friendly comments
* Added an additional test to check current row ranges are set correctly doing an update and removed a redundant delete test

Co-authored-by: Marcos César de Oliveira <[email protected]>
Co-authored-by: Levente A <[email protected]>
Co-authored-by: Simone Busoli <[email protected]>

.gitignore

@@ -1,3 +1,5 @@
 *.tmp
 .DS_Store
-test/result
+test/result
+.env
+.envrc

README.md

@@ -11,6 +11,7 @@ For a speedier but riskier option, `versioning_function_nochecks.sql` is 2x fast
 Over time, new features have been introduced while maintaining backward compatibility:
 
 - [Ignore updates with no actual changes](#ignore-unchanged-values)
+- [Include the current version in history](#include-current-version-in-history)
 
 <a name="usage"></a>
 
@@ -184,6 +185,43 @@ FOR EACH ROW EXECUTE PROCEDURE versioning(
 );
 ```
 
+
+<a name="include-current-version-in-history"></a>
+
+### Include the current version in history
+
+By default this extension only creates a record in the history table for historical records. This feature enables users to also store the details of the current record in the history table. Simplifying cases when you want a consolidated view of both the current and historical states.
+
+e.g
+
+```sql
+SELECT * FROM t_history WHERE x <@ sys_period;
+```
+when `include_current_version_in_history` is true
+
+as opposed to
+
+``` sql
+SELECT * FROM t WHERE x <@ sys_period
+UNION
+SELECT * FROM t_history WHERE x <@ sys_period;
+```
+when `include_current_version_in_history` is false (or unset)
+
+This is a fith parameter in the extension so all previous parameters need to be specified when using this.
+
+The parameter is set by default to false, set it to true to include current version of records in the history table.
+
+``` sql
+CREATE TRIGGER versioning_trigger
+BEFORE INSERT OR UPDATE OR DELETE ON subscriptions
+FOR EACH ROW EXECUTE PROCEDURE versioning(
+  'sys_period', 'subscriptions_history', true, false, true
+);
+```
+
+
+
 <a name="migrations"></a>
 
 ## Migrations

test/expected/noop_update.out

@@ -0,0 +1,21 @@
+-- No-op Update Test
+CREATE TABLE versioning_noop (a bigint, "b b" date, sys_period tstzrange);
+-- Insert initial data.
+INSERT INTO versioning_noop (a, "b b", sys_period) VALUES (1, '2020-01-01', tstzrange('2000-01-01', NULL));
+CREATE TABLE versioning_noop_history (a bigint, "b b" date, sys_period tstzrange);
+CREATE TRIGGER versioning_noop_trigger
+BEFORE INSERT OR UPDATE OR DELETE ON versioning_noop
+FOR EACH ROW EXECUTE PROCEDURE versioning('sys_period', 'versioning_noop_history', false, true, true);
+-- Test no-op update (the row is updated without any value changes).
+BEGIN;
+UPDATE versioning_noop SET a = 1, "b b" = '2020-01-01' WHERE a = 1;
+-- Check that no history record was created.
+SELECT * FROM versioning_noop_history;  -- Expecting 0 rows in history.
+ a | b b | sys_period 
+---+-----+------------
+(0 rows)
+
+COMMIT;
+-- Cleanup
+DROP TABLE versioning_noop;
+DROP TABLE versioning_noop_history;

test/expected/set_system_time.out

@@ -27,7 +27,7 @@ UPDATE versioning SET a = 4 WHERE a = 3;
 SELECT * FROM versioning_history;
  a | c |         sys_period          
 ---+---+------------------------------------
- 3 |   | (,"2001-01-01 22:59:59.001234+01")
+ 3 |   | (,"2001-01-01 22:59:59.001234+00")
 (1 row)
 
 COMMIT;
@@ -38,8 +38,8 @@ UPDATE versioning SET "b b" = '2012-01-01' WHERE a = 5;
 SELECT * FROM versioning_history;
  a | c |         sys_period          
 ---+---+------------------------------------
- 3 |   | (,"2001-01-01 22:59:59.001234+01")
- 4 |   | (,"2001-01-01 22:59:59.001234+01")
+ 3 |   | (,"2001-01-01 22:59:59.001234+00")
+ 4 |   | (,"2001-01-01 22:59:59.001234+00")
 (2 rows)
 
 COMMIT;
@@ -55,8 +55,8 @@ DELETE FROM versioning WHERE a = 4;
 SELECT * FROM versioning_history;
  a | c |         sys_period          
 ---+---+------------------------------------
- 3 |   | (,"2001-01-01 22:59:59.001234+01")
- 4 |   | (,"2001-01-01 22:59:59.001234+01")
+ 3 |   | (,"2001-01-01 22:59:59.001234+00")
+ 4 |   | (,"2001-01-01 22:59:59.001234+00")
 (2 rows)
 
 END;
@@ -66,11 +66,11 @@ DELETE FROM versioning;
 SELECT * FROM versioning_history;
  a | c |         sys_period          
 ---+---+------------------------------------
- 3 |   | (,"2001-01-01 22:59:59.001234+01")
- 4 |   | (,"2001-01-01 22:59:59.001234+01")
- 1 |   | (,"2022-01-11 12:00:00+01")
- 2 |   | (,"2022-01-11 12:00:00+01")
- 5 |   | (,"2022-01-11 12:00:00+01")
+ 3 |   | (,"2001-01-01 22:59:59.001234+00")
+ 4 |   | (,"2001-01-01 22:59:59.001234+00")
+ 1 |   | (,"2022-01-11 12:00:00+00")
+ 2 |   | (,"2022-01-11 12:00:00+00")
+ 5 |   | (,"2022-01-11 12:00:00+00")
 (5 rows)
 
 END;

test/expected/versioning_including_current_version_in_history.out

@@ -0,0 +1,160 @@
+CREATE TABLE versioning (a bigint, "b b" date, sys_period tstzrange);
+-- Insert some data before versioning is enabled.
+INSERT INTO versioning (a, sys_period) VALUES (1, tstzrange('-infinity', NULL));
+INSERT INTO versioning (a, sys_period) VALUES (2, tstzrange('2000-01-01', NULL));
+CREATE TABLE versioning_history (a bigint, c date, sys_period tstzrange);
+CREATE TRIGGER versioning_trigger
+BEFORE INSERT OR UPDATE OR DELETE ON versioning
+FOR EACH ROW EXECUTE PROCEDURE versioning('sys_period', 'versioning_history', false, false, true);
+-- Insert.
+BEGIN;
+INSERT INTO versioning (a) VALUES (3);
+SELECT a, "b b", lower(sys_period) = CURRENT_TIMESTAMP FROM versioning ORDER BY a, sys_period;
+ a | b b | ?column?
+---+-----+----------
+ 1 |     | f
+ 2 |     | f
+ 3 |     | t
+(3 rows)
+
+SELECT a, c, lower(sys_period) = CURRENT_TIMESTAMP FROM versioning_history ORDER BY a, sys_period;
+ a | c | ?column?
+---+---+----------
+ 3 |   | t
+(1 row)
+
+COMMIT;
+-- Make sure that the next transaction's CURRENT_TIMESTAMP is different.
+SELECT pg_sleep(0.1);
+ pg_sleep
+----------
+
+(1 row)
+
+-- Update.
+BEGIN;
+UPDATE versioning SET a = 4 WHERE a = 3;
+SELECT a, "b b", lower(sys_period) = CURRENT_TIMESTAMP FROM versioning ORDER BY a, sys_period;
+ a | b b | ?column?
+---+-----+----------
+ 1 |     | f
+ 2 |     | f
+ 4 |     | t
+(3 rows)
+
+SELECT a, c, upper(sys_period) = CURRENT_TIMESTAMP FROM versioning_history ORDER BY a, sys_period;
+ a | c | ?column?
+---+---+----------
+ 3 |   | t
+ 4 |   |
+(2 rows)
+
+SELECT a, c, lower(sys_period) = CURRENT_TIMESTAMP FROM versioning_history ORDER BY a, sys_period;
+ a | c | ?column?
+---+---+----------
+ 3 |   | 
+ 4 |   | t
+(2 rows)
+
+SELECT a, "b b" FROM versioning WHERE lower(sys_period) = CURRENT_TIMESTAMP ORDER BY a, sys_period;
+ a | b b
+---+-----
+ 4 |
+(1 row)
+
+COMMIT;
+-- Make sure that the next transaction's CURRENT_TIMESTAMP is different.
+SELECT pg_sleep(0.1);
+ pg_sleep
+----------
+
+(1 row)
+
+-- Multiple updates.
+BEGIN;
+UPDATE versioning SET a = 5 WHERE a = 4;
+UPDATE versioning SET "b b" = '2012-01-01' WHERE a = 5;
+SELECT a, "b b", lower(sys_period) = CURRENT_TIMESTAMP FROM versioning ORDER BY a, sys_period;
+ a |    b b     | ?column?
+---+------------+----------
+ 1 |            | f
+ 2 |            | f
+ 5 | 2012-01-01 | t
+(3 rows)
+
+SELECT a, c, upper(sys_period) = CURRENT_TIMESTAMP FROM versioning_history ORDER BY a, sys_period;
+ a | c | ?column?
+---+---+----------
+ 3 |   | f
+ 4 |   | t
+ 5 |   | t
+ 5 |   |
+(4 rows)
+
+SELECT a, "b b" FROM versioning WHERE lower(sys_period) = CURRENT_TIMESTAMP ORDER BY a, sys_period;
+ a |    b b
+---+------------
+ 5 | 2012-01-01
+(1 row)
+
+COMMIT;
+-- Make sure that the next transaction's CURRENT_TIMESTAMP is different.
+SELECT pg_sleep(0.1);
+ pg_sleep
+----------
+
+(1 row)
+
+-- Delete.
+BEGIN;
+DELETE FROM versioning WHERE a = 4;
+SELECT a, "b b", lower(sys_period) = CURRENT_TIMESTAMP FROM versioning ORDER BY a, sys_period;
+ a |    b b     | ?column?
+---+------------+----------
+ 1 |            | f
+ 2 |            | f
+ 5 | 2012-01-01 | f
+(3 rows)
+
+SELECT a, c, upper(sys_period) = CURRENT_TIMESTAMP FROM versioning_history ORDER BY a, sys_period;
+ a | c | ?column?
+---+---+----------
+ 3 |   | f
+ 4 |   | f
+ 5 |   | f
+ 5 |   |
+(4 rows)
+
+SELECT a, "b b" FROM versioning WHERE lower(sys_period) = CURRENT_TIMESTAMP ORDER BY a, sys_period;
+ a | b b
+---+-----
+(0 rows)
+
+END;
+-- Make sure that the next transaction's CURRENT_TIMESTAMP is different.
+SELECT pg_sleep(0.1);
+ pg_sleep
+----------
+
+(1 row)
+
+-- Delete.
+BEGIN;
+DELETE FROM versioning;
+SELECT * FROM versioning;
+ a | b b | sys_period
+---+-----+------------
+(0 rows)
+
+SELECT a, c, upper(sys_period) = CURRENT_TIMESTAMP FROM versioning_history ORDER BY a, sys_period;
+ a | c | ?column?
+---+---+----------
+ 3 |   | f
+ 4 |   | f
+ 5 |   | f
+ 5 |   | t
+(4 rows)
+
+END;
+DROP TABLE versioning;
+DROP TABLE versioning_history;

test/expected/versioning_rollback_include_current_version_in_history.out

@@ -0,0 +1,29 @@
+-- Rollback Behavior Test
+CREATE TABLE versioning_rollback (a bigint, "b b" date, sys_period tstzrange);
+-- Insert initial data.
+INSERT INTO versioning_rollback (a, "b b", sys_period) VALUES (1, '2020-01-01', tstzrange('2000-01-01', NULL));
+CREATE TABLE versioning_rollback_history (a bigint, "b b" date, sys_period tstzrange);
+CREATE TRIGGER versioning_rollback_trigger
+BEFORE INSERT OR UPDATE OR DELETE ON versioning_rollback
+FOR EACH ROW EXECUTE PROCEDURE versioning('sys_period', 'versioning_rollback_history', false, false, true);
+-- Test rollback during update.
+BEGIN;
+UPDATE versioning_rollback SET a = 2 WHERE a = 1;
+-- Rollback the transaction.
+ROLLBACK;
+-- Ensure no history record was created.
+SELECT * FROM versioning_rollback_history;  -- Expecting 0 rows in history.
+ a | b b | sys_period 
+---+-----+------------
+(0 rows)
+
+-- Ensure original data is unchanged.
+SELECT * FROM versioning_rollback;  -- Expecting original value a = 1.
+ a |    b b     |         sys_period          
+---+------------+-----------------------------
+ 1 | 2020-01-01 | ["2000-01-01 00:00:00+00",)
+(1 row)
+
+-- Cleanup
+DROP TABLE versioning_rollback;
+DROP TABLE versioning_rollback_history;

test/runTest.sh

@@ -12,7 +12,8 @@ TESTS="
   versioning upper_case structure combinations
   different_schema unchanged_values unchanged_version_values
   non_equality_types non_equality_types_unchanged_values
-  set_system_time invalid_set_system_time
+  set_system_time invalid_set_system_time versioning_including_current_version_in_history
+  versioning_rollback_include_current_version_in_history noop_update
   "
 
 for name in $TESTS; do

test/runTestNochecks.sh

@@ -9,7 +9,8 @@ mkdir -p test/result
 TESTS="
   versioning upper_case structure combinations different_schema unchanged_values
   non_equality_types non_equality_types_unchanged_values
-  unchanged_version_values
+  unchanged_version_values versioning_including_current_version_in_history
+  versioning_rollback_include_current_version_in_history noop_update
   "
 
 for name in $TESTS; do

test/sql/noop_update.sql

@@ -0,0 +1,25 @@
+-- No-op Update Test
+CREATE TABLE versioning_noop (a bigint, "b b" date, sys_period tstzrange);
+
+-- Insert initial data.
+INSERT INTO versioning_noop (a, "b b", sys_period) VALUES (1, '2020-01-01', tstzrange('2000-01-01', NULL));
+
+CREATE TABLE versioning_noop_history (a bigint, "b b" date, sys_period tstzrange);
+
+CREATE TRIGGER versioning_noop_trigger
+BEFORE INSERT OR UPDATE OR DELETE ON versioning_noop
+FOR EACH ROW EXECUTE PROCEDURE versioning('sys_period', 'versioning_noop_history', false, true, true);
+
+-- Test no-op update (the row is updated without any value changes).
+BEGIN;
+
+UPDATE versioning_noop SET a = 1, "b b" = '2020-01-01' WHERE a = 1;
+
+-- Check that no history record was created.
+SELECT * FROM versioning_noop_history;  -- Expecting 0 rows in history.
+
+COMMIT;
+
+-- Cleanup
+DROP TABLE versioning_noop;
+DROP TABLE versioning_noop_history;