fix(syntax): correct parentheses around union (#9813) (#10003) (#10121)

lib/dialects/abstract/query-generator.js

@@ -1096,7 +1096,7 @@ const QueryGenerator = {
 
         // Caching the base query and splicing the where part into it is consistently > twice
         // as fast than generating from scratch each time for values.length >= 5
-        const baseQuery = '(' + this.selectQuery(
+        const baseQuery = 'SELECT * FROM (' + this.selectQuery(
           tableName,
           {
             attributes: options.attributes,
@@ -1107,7 +1107,7 @@ const QueryGenerator = {
             model
           },
           model
-        ).replace(/;$/, '') + ')';
+        ).replace(/;$/, '') + ') AS sub'; // Every derived table must have its own alias
         const placeHolder = this.whereItemQuery(Op.placeholder, true, { model });
         const splicePos = baseQuery.indexOf(placeHolder);
 

test/integration/model/findAll/separate.test.js

+'use strict';
+
+const chai = require('chai');
+const expect = chai.expect;
+const Support = require('../../support');
+const DataTypes = require('../../../../lib/data-types');
+const Sequelize = require('../../../../lib/sequelize');
+const current = Support.sequelize;
+
+describe(Support.getTestDialectTeaser('Model'), () => {
+  describe('findAll', () => {
+    describe('separate with limit', () => {
+      it('should not throw syntax error (union)', () => {
+        // #9813 testcase
+        const Project = current.define('Project', { name: DataTypes.STRING });
+        const LevelTwo = current.define('LevelTwo', { name: DataTypes.STRING });
+        const LevelThree = current.define('LevelThree', { type: DataTypes.INTEGER });
+
+        Project.hasMany(LevelTwo);
+        LevelTwo.belongsTo(Project);
+
+        LevelTwo.hasMany(LevelThree, { as: 'type_ones' });
+        LevelTwo.hasMany(LevelThree, { as: 'type_twos' });
+        LevelThree.belongsTo(LevelTwo);
+
+        return current.sync({ force: true }).then(() => {
+          return Sequelize.Promise.all([
+            Project.create({ name: 'testProject' }),
+            LevelTwo.create({ name: 'testL21' }),
+            LevelTwo.create({ name: 'testL22' })
+          ]);
+        }).spread((project, level21, level22) => {
+          return Sequelize.Promise.all([
+            project.addLevelTwo(level21),
+            project.addLevelTwo(level22)
+          ]);
+        }).spread(() => {
+          // one include case
+          return Project.findAll({
+            where: { name: 'testProject' },
+            include: [
+              {
+                model: LevelTwo,
+                include: [
+                  {
+                    model: LevelThree,
+                    as: 'type_ones',
+                    where: { type: 0 },
+                    separate: true,
+                    limit: 1,
+                    order: [['createdAt', 'DESC']]
+                  }
+                ]
+              }
+            ]
+          });
+        }).then(projects => {
+          expect(projects).to.have.length(1);
+          expect(projects[0].LevelTwos).to.have.length(2);
+          expect(projects[0].LevelTwos[0].type_ones).to.have.length(0);
+          expect(projects[0].LevelTwos[1].type_ones).to.have.length(0);
+        }, () => {
+          expect.fail();
+        }).then(() => {
+          // two includes case
+          return Project.findAll({
+            where: { name: 'testProject' },
+            include: [
+              {
+                model: LevelTwo,
+                include: [
+                  {
+                    model: LevelThree,
+                    as: 'type_ones',
+                    where: { type: 0 },
+                    separate: true,
+                    limit: 1,
+                    order: [['createdAt', 'DESC']]
+                  },
+                  {
+                    model: LevelThree,
+                    as: 'type_twos',
+                    where: { type: 1 },
+                    separate: true,
+                    limit: 1,
+                    order: [['createdAt', 'DESC']]
+                  }
+                ]
+              }
+            ]
+          });
+        }).then(projects => {
+          expect(projects).to.have.length(1);
+          expect(projects[0].LevelTwos).to.have.length(2);
+          expect(projects[0].LevelTwos[0].type_ones).to.have.length(0);
+          expect(projects[0].LevelTwos[1].type_ones).to.have.length(0);
+        }, () => {
+          expect.fail();
+        });
+      });
+    });
+  });
+});