PostgreSQL: Edit and delete rows of a partitioned table

limit1() identifies the row by its ctid, which is unique only within a
single relation. A partitioned table is not one relation, so the
condition is evaluated in every partition and matches whatever row sits
at the same (block, offset) in each of them. Editing or deleting one row
of a table with 64 partitions can affect 64 rows.

The ctid is used only when the row has no unique key, which is also the
case where the damage goes unnoticed - the affected rows are unrelated to
the edited one.

Matching (tableoid, ctid) restricts the condition to the partition
holding the row. tableoid is a system column of every table, so the
statement keeps its behaviour on ordinary tables, and tables using
INHERITS are fixed as well.

Author: davidkrmela

CHANGELOG.md

@@ -6,6 +6,7 @@
 - Cache the assets of the compiled version in a service worker
 - MySQL: Display the check constraint clause without the extra escaping added by information_schema
 - MySQL 9: Create routines with LANGUAGE JAVASCRIPT
+- PostgreSQL: Edit and delete only the selected row of a partitioned table without a unique key, rows in the other partitions were affected too
 - MS SQL: Get the base type of a column declared with a user-defined type
 - ClickHouse: Print only errors from ClickHouse (GHSA-77qq-q8fv-x45v, regression from 6.0.0)
 - ClickHouse: Highlight the queries

adminer/drivers/pgsql.inc.php

@@ -490,7 +490,7 @@ function limit(string $query, string $where, int $limit, int $offset = 0, string
 	function limit1(string $table, string $query, string $where, string $separator = "\n"): string {
 		return (preg_match('~^INTO~', $query)
 			? limit($query, $where, 1, 0, $separator)
-			: " $query" . (is_view(table_status1($table)) ? $where : $separator . "WHERE ctid = (SELECT ctid FROM " . table($table) . $where . $separator . "LIMIT 1)")
+			: " $query" . (is_view(table_status1($table)) ? $where : $separator . "WHERE (tableoid, ctid) = (SELECT tableoid, ctid FROM " . table($table) . $where . $separator . "LIMIT 1)")
 		);
 	}
 

tests/pgsql.spec.js

@@ -588,6 +588,29 @@ test('Partitioning', async () => {
 	await expect(page.locator('body')).toContainText('No tables.');
 });
 
+test('Partitioned rows', async () => {
+	const sql = "CREATE TABLE parts (id int, val text) PARTITION BY LIST (id);"
+		+ " CREATE TABLE parts_1 PARTITION OF parts FOR VALUES IN (1);"
+		+ " CREATE TABLE parts_2 PARTITION OF parts FOR VALUES IN (2);"
+		+ " INSERT INTO parts VALUES (1, 'one'), (2, 'two')"; // both rows are the first one in their partition, so they share the ctid
+	await goto(page, '/adminer/?pgsql=&username=ODBC&db=adminer_test&ns=public&sql=' + encodeURIComponent(sql));
+	await button(page, 'Execute').click();
+	await expect(page.locator('body')).toContainText('Query executed OK');
+	const select = '/adminer/?pgsql=&username=ODBC&db=adminer_test&ns=public&select=parts&order[0]=id';
+	await goto(page, select);
+	await link(page, 'edit').click(); // the table has no unique key, so the row is identified by the ctid, which is unique only within a partition
+	await page.locator('[name="fields[val]"]').fill('uno');
+	await button(page, 'Save').click();
+	await expect(page.locator('body')).toContainText('Item has been updated.');
+	await goto(page, select);
+	await expect(page.locator('body')).toContainText('two'); // the row in the other partition must keep its value
+	await page.locator('input[name="check[]"]').first().click();
+	await page.locator('[name="delete"]').click();
+	await expect(page.locator('body')).toContainText('1 item has been affected.');
+	await goto(page, '/adminer/?pgsql=&username=ODBC&db=adminer_test&ns=public&sql=' + encodeURIComponent('DROP TABLE parts'));
+	await button(page, 'Execute').click();
+});
+
 test('Variables', async () => {
 	await goto(page, '/adminer/?pgsql=&username=ODBC&variables=');
 	await expect(page.locator('body')).toContainText('autovacuum');