fix: Do not add NULL/NOT NULL for stored columns (#7708)

closes: #7698

src/driver/mysql/MysqlQueryRunner.ts

@@ -1867,8 +1867,8 @@ export class MysqlQueryRunner extends BaseQueryRunner implements QueryRunner {
             c += ` COLLATE "${column.collation}"`;
 
         const isMariaDb = this.driver.options.type === "mariadb";
-        if (isMariaDb && column.asExpression && (column.generatedType || "VIRTUAL") === "VIRTUAL") {
-            // do nothing - MariaDB does not support NULL/NOT NULL expressions for VIRTUAL columns
+        if (isMariaDb && column.asExpression && ["VIRTUAL", "STORED"].includes((column.generatedType || "VIRTUAL"))) {
+            // do nothing - MariaDB does not support NULL/NOT NULL expressions for VIRTUAL columns and STORED columns
         } else {
             if (!column.isNullable)
                 c += " NOT NULL";

test/github-issues/7698/entity/Test.ts

@@ -0,0 +1,21 @@
+import { Column, Entity, PrimaryGeneratedColumn } from "../../../../src";
+
+@Entity()
+export class Test {
+
+  @PrimaryGeneratedColumn({ type: 'int' })
+  id: number;
+
+  @Column()
+  firstName: string
+
+  @Column()
+  lastName: string
+
+  @Column({
+    generatedType: 'STORED',
+    // asExpression is needed here or generatedType above will be ignored
+    asExpression: "concat(`firstName`,' ',`lastName`)",
+  })
+  name: string;
+}

test/github-issues/7698/issue-7698.ts

@@ -0,0 +1,25 @@
+import "reflect-metadata";
+import { Connection } from "../../../src";
+import { closeTestingConnections, createTestingConnections, reloadTestingDatabases } from "../../utils/test-utils";
+import { Test } from "./entity/Test";
+
+describe("github issues > #7698 MariaDB STORED columns don't accept [NULL | NOT NULL]", () => {
+
+    let connections: Connection[];
+    before(async () => {
+        connections = await createTestingConnections({
+            enabledDrivers: ["mariadb"],
+            entities: [Test],
+            schemaCreate: false,
+            dropSchema: true
+        });
+    });
+    beforeEach(() => reloadTestingDatabases(connections));
+    after(() => closeTestingConnections(connections));
+
+    it("should not generate queries with NULL or NOT NULL for stored columns in mariadb", () => Promise.all(connections.map(async connection => {
+        await connection.driver.createSchemaBuilder().build();
+        const sqlInMemory = await connection.driver.createSchemaBuilder().log();
+        sqlInMemory.upQueries.length.should.be.greaterThan(0);
+    })));
+});