diff --git a/.github/workflows/test-and-release.yml b/.github/workflows/test-and-release.yml
index 25befe3..de78ff8 100644
--- a/.github/workflows/test-and-release.yml
+++ b/.github/workflows/test-and-release.yml
@@ -200,7 +200,7 @@ jobs:
             # @iobroker/adapter-core, which calls process.exit(10) when js-controller cannot be
             # resolved, and js-controller is not a dependency of this repository.
             - name: Run unit tests
-              run: node node_modules/mocha/bin/mocha test/testCommons.js test/testIntegral.js test/testDockerCompose.js test/testErrors.js test/testSqlClient.js test/testConnectionOptions.js test/testMessageGuard.js test/testStatistics.js test/testPackageFiles.js --exit
+              run: node node_modules/mocha/bin/mocha test/testCommons.js test/testIntegral.js test/testDockerCompose.js test/testErrors.js test/testSqlClient.js test/testConnectionOptions.js test/testMessageGuard.js test/testStatistics.js test/testInsertStatements.js test/testPackageFiles.js --exit
 
             - name: Run SQLite tests
               run: node node_modules/mocha/bin/mocha test/testSQLite.js --exit
diff --git a/test/testInsertStatements.js b/test/testInsertStatements.js
new file mode 100644
index 0000000..b68e7e6
--- /dev/null
+++ b/test/testInsertStatements.js
@@ -0,0 +1,83 @@
+const assert = require('node:assert');
+
+// Imported per dialect, never from build/main: that would pull in @iobroker/adapter-core, which
+// calls process.exit(10) when js-controller cannot be resolved.
+const DIALECTS = {
+    mysql: require('../build/lib/mysql'),
+    postgresql: require('../build/lib/postgresql'),
+    mssql: require('../build/lib/mssql'),
+    sqlite: require('../build/lib/sqlite'),
+};
+
+// A statement that carries a second one after a semicolon. The trailing semicolon of the statement
+// itself is not a match - only a semicolon with another statement behind it.
+const CONCATENATED = /;\s*(INSERT|SELECT|UPDATE|DELETE)/i;
+
+function rows() {
+    // The batch from issue #294: a counter datapoint produces rows in ts_counter *and* ts_number
+    // within the same flush, which is what used to end up in one query.
+    return [
+        { table: 'ts_counter', state: { val: 53.32, ts: 1676135872618 }, from: 2 },
+        { table: 'ts_counter', state: { val: 53, ts: 1676138387812 }, from: 2 },
+        { table: 'ts_number', state: { val: 53, ts: 1676138387812, ack: true }, from: 2 },
+        { table: 'ts_counter', state: { val: 52.95, ts: 1676138670902 }, from: 2 },
+        { table: 'ts_number', state: { val: 52.95, ts: 1676138670902, ack: true }, from: 2 },
+    ];
+}
+
+describe('Test insert() never concatenates statements', function () {
+    for (const [dialect, sql] of Object.entries(DIALECTS)) {
+        it(`${dialect}: emits one statement per table instead of one joined query`, function () {
+            const queries = sql.insert('iobroker', 5, rows());
+
+            assert.ok(Array.isArray(queries), 'insert() returns a list of statements');
+            assert.strictEqual(queries.length, 2, `ts_counter and ts_number, got ${queries.length}`);
+
+            // This is issue #294: the adapter used to send
+            //   INSERT INTO ...ts_counter ...;INSERT INTO ...ts_number ...;
+            // as a single query, which MariaDB rejects with a syntax error because no driver here
+            // is configured for multi-statement batches.
+            for (const query of queries) {
+                assert.ok(!CONCATENATED.test(query), `carries a second statement: ${query}`);
+                assert.strictEqual((query.match(/INSERT/gi) || []).length, 1, `more than one INSERT in: ${query}`);
+            }
+
+            const tables = queries.map(q => (q.match(/ts_\w+/) || [])[0]);
+            assert.deepStrictEqual([...tables].sort(), ['ts_counter', 'ts_number']);
+        });
+
+        it(`${dialect}: keeps the statements apart for every table`, function () {
+            const queries = sql.insert('iobroker', 5, [
+                { table: 'ts_number', state: { val: 1, ts: 1, ack: true }, from: 2 },
+                { table: 'ts_string', state: { val: 'x', ts: 2, ack: true }, from: 2 },
+                { table: 'ts_bool', state: { val: true, ts: 3, ack: true }, from: 2 },
+                { table: 'ts_counter', state: { val: 4, ts: 4 }, from: 2 },
+            ]);
+
+            assert.strictEqual(queries.length, 4, 'one per table');
+            for (const query of queries) {
+                assert.ok(!CONCATENATED.test(query), `carries a second statement: ${query}`);
+            }
+        });
+
+        it(`${dialect}: chunks a large batch without joining the chunks`, function () {
+            const many = [];
+            for (let i = 0; i < 1200; i++) {
+                many.push({ table: 'ts_number', state: { val: i, ts: 1700000000000 + i, ack: true }, from: 2 });
+            }
+
+            const queries = sql.insert('iobroker', 5, many);
+
+            // 500 rows per statement, so the chunks must stay separate queries rather than being
+            // glued back together with semicolons.
+            assert.strictEqual(queries.length, 3, `expected 500/500/200, got ${queries.length} chunks`);
+            for (const query of queries) {
+                assert.ok(!CONCATENATED.test(query), `carries a second statement: ${query}`);
+                assert.strictEqual((query.match(/INSERT/gi) || []).length, 1);
+            }
+
+            const tuples = queries.map(q => (q.match(/\),\(/g) || []).length + 1);
+            assert.deepStrictEqual(tuples, [500, 500, 200]);
+        });
+    }
+});