Fix SERIAL columns to respect explicitly provided values including NULL

src/60createtable.js

@@ -356,7 +356,10 @@ yy.CreateTable.prototype.execute = function (databaseid, params, cb) {
 		for (var columnid in table.identities) {
 			var ident = table.identities[columnid];
 			//			console.log(ident);
-			r[columnid] = ident.value;
+			// Only auto-assign identity value if not explicitly provided or if NULL
+			if (typeof r[columnid] === 'undefined' || r[columnid] === null) {
+				r[columnid] = ident.value;
+			}
 			//			console.log(ident);
 		}
 		//console.log(270,r);
@@ -420,7 +423,17 @@ yy.CreateTable.prototype.execute = function (databaseid, params, cb) {
 			for (var columnid in table.identities) {
 				var ident = table.identities[columnid];
 				//			console.log(ident);
-				ident.value += ident.step;
+				// Only increment if we used the auto-generated value
+				// If user provided explicit value >= current counter, update counter
+				if (
+					typeof r[columnid] !== 'undefined' &&
+					r[columnid] !== null &&
+					+r[columnid] >= ident.value
+				) {
+					ident.value = +r[columnid] + ident.step;
+				} else {
+					ident.value += ident.step;
+				}
 				//			console.log(ident);
 			}
 

test/test895.js

@@ -0,0 +1,122 @@
+if (typeof exports === 'object') {
+	var assert = require('assert');
+	var alasql = require('..');
+}
+
+describe('Test 895 - SERIAL type should not overwrite explicitly provided values', function () {
+	const testId = '895';
+
+	before(() => {
+		alasql('create database test' + testId);
+		alasql('use test' + testId);
+	});
+
+	after(() => {
+		alasql('drop database test' + testId);
+	});
+
+	it('A) SERIAL column should auto-increment when not provided', () => {
+		alasql(`
+			CREATE TABLE users (id serial, name varchar(50));
+			INSERT INTO users (name) VALUES ("first");
+			INSERT INTO users (name) VALUES ("second");
+			INSERT INTO users (name) VALUES ("third");
+		`);
+		var res = alasql('SELECT * FROM users ORDER BY id');
+		assert.deepEqual(res, [
+			{id: 1, name: 'first'},
+			{id: 2, name: 'second'},
+			{id: 3, name: 'third'},
+		]);
+	});
+
+	it('B) SERIAL column should accept explicitly provided value', () => {
+		alasql(`
+			CREATE TABLE products (id serial, name varchar(50));
+			INSERT INTO products (id, name) VALUES (10, "first");
+			INSERT INTO products (id, name) VALUES (20, "second");
+			INSERT INTO products (id, name) VALUES (30, "third");
+		`);
+		var res = alasql('SELECT * FROM products ORDER BY id');
+		assert.deepEqual(res, [
+			{id: 10, name: 'first'},
+			{id: 20, name: 'second'},
+			{id: 30, name: 'third'},
+		]);
+	});
+
+	it('C) SERIAL column should accept explicitly provided value even if lower than counter', () => {
+		alasql(`
+			CREATE TABLE orders (id serial, name varchar(50));
+			INSERT INTO orders (name) VALUES ("auto1");
+			INSERT INTO orders (name) VALUES ("auto2");
+			INSERT INTO orders (name) VALUES ("auto3");
+			INSERT INTO orders (id, name) VALUES (100, "explicit");
+		`);
+		var res = alasql('SELECT * FROM orders ORDER BY id');
+		assert.deepEqual(res, [
+			{id: 1, name: 'auto1'},
+			{id: 2, name: 'auto2'},
+			{id: 3, name: 'auto3'},
+			{id: 100, name: 'explicit'},
+		]);
+	});
+
+	it('D) SERIAL with mixed auto and explicit values', () => {
+		alasql(`
+			CREATE TABLE customers (id serial, name varchar(50));
+			INSERT INTO customers (id, name) VALUES (5, "explicit5");
+			INSERT INTO customers (name) VALUES ("auto");
+			INSERT INTO customers (id, name) VALUES (10, "explicit10");
+			INSERT INTO customers (name) VALUES ("auto2");
+		`);
+		var res = alasql('SELECT * FROM customers ORDER BY id');
+		assert.deepEqual(res, [
+			{id: 5, name: 'explicit5'},
+			{id: 6, name: 'auto'},
+			{id: 10, name: 'explicit10'},
+			{id: 11, name: 'auto2'},
+		]);
+	});
+
+	it('E) Bulk insert with explicit SERIAL values', () => {
+		alasql(`
+			CREATE TABLE items (id serial, name varchar(50));
+			INSERT INTO items (id, name) VALUES (4, "item4"), (8, "item8"), (12, "item12");
+		`);
+		var res = alasql('SELECT * FROM items ORDER BY id');
+		assert.deepEqual(res, [
+			{id: 4, name: 'item4'},
+			{id: 8, name: 'item8'},
+			{id: 12, name: 'item12'},
+		]);
+	});
+
+	it('F) Re-inserting data after truncate with explicit IDs', () => {
+		alasql(`
+			CREATE TABLE records (id serial, name varchar(50));
+			INSERT INTO records (name) VALUES ("first"), ("second"), ("third");
+		`);
+		var res1 = alasql('SELECT * FROM records ORDER BY id');
+		assert.deepEqual(res1, [
+			{id: 1, name: 'first'},
+			{id: 2, name: 'second'},
+			{id: 3, name: 'third'},
+		]);
+
+		// Simulate the flush scenario from the issue
+		alasql(`
+			DELETE FROM records;
+			INSERT INTO records (id, name) VALUES (4, "item4");
+			INSERT INTO records (id, name) VALUES (7, "item7");
+			INSERT INTO records (id, name) VALUES (9, "item9");
+		`);
+
+		var res2 = alasql('SELECT * FROM records ORDER BY id');
+		assert.deepEqual(res2, [
+			{id: 4, name: 'item4'},
+			{id: 7, name: 'item7'},
+			{id: 9, name: 'item9'},
+		]);
+	});
+});