Improve error message of foreign key violation to fix #1009 (#2206)

Co-authored-by: copilot-swe-agent[bot] <[email protected]>
Co-authored-by: mathiasrw <[email protected]>

Author: Copilot

src/60createtable.js

@@ -175,7 +175,7 @@ yy.CreateTable.prototype.execute = function (databaseid, params, cb) {
 					var addr = fktable.pk.onrightfn(rr);
 					if (!fktable.uniqs[fktable.pk.hh][addr]) {
 						throw new Error(
-							'Foreign key violation' //changed error message
+							'Foreign key "' + r[col.columnid] + '" not found in table "' + fk.tableid + '"'
 						);
 					}
 					return true;
@@ -265,8 +265,11 @@ yy.CreateTable.prototype.execute = function (databaseid, params, cb) {
 				var addr = fktable.pk.onrightfn(rr);
 
 				if (!fktable.uniqs[fktable.pk.hh][addr]) {
+					var keyValues = fk.columns.map(function (col) {
+						return r[col];
+					});
 					throw new Error(
-						'Foreign key violation' //changed error message
+						'Foreign key "' + keyValues.join(', ') + '" not found in table "' + fk.tableid + '"'
 					);
 				}
 				return true;

test/test1009.js

@@ -0,0 +1,89 @@
+if (typeof exports === 'object') {
+	var assert = require('assert');
+	var alasql = require('..');
+}
+
+describe('Test 1009 - Foreign key error message with table name', function () {
+	const test = '1009';
+
+	before(function () {
+		alasql('create database test' + test);
+		alasql('use test' + test);
+	});
+
+	after(function () {
+		alasql('drop database test' + test);
+	});
+
+	it('A) Single column foreign key - error message should include table and key', function () {
+		alasql(
+			'CREATE TABLE tableA (id INT PRIMARY KEY);' +
+				'CREATE TABLE tableB (id INT, a_id INT, FOREIGN KEY (a_id) REFERENCES tableA(id));' +
+				'INSERT INTO tableA VALUES (1);' +
+				'INSERT INTO tableA VALUES (2);' +
+				'INSERT INTO tableB VALUES (1, 1);'
+		);
+
+		// This should fail with a proper error message showing the table name and key
+		try {
+			alasql('INSERT INTO tableB VALUES (2, 20)');
+			assert.fail('Should have thrown an error for foreign key violation');
+		} catch (err) {
+			console.log('Error message:', err.message);
+			// The error message should include information about what key and table failed
+			assert(err.message.includes('Foreign key'), 'Error should mention foreign key');
+			assert(err.message.includes('20'), 'Error should include the key value');
+			assert(err.message.includes('tableA'), 'Error should include the table name');
+			// Check that it's not showing 'undefined' as the table name
+			assert(!err.message.includes('undefined'), 'Error should not contain undefined');
+		}
+	});
+
+	it('B) Inline foreign key - error message should include table and key', function () {
+		alasql(
+			'DROP TABLE IF EXISTS tableC;' +
+				'DROP TABLE IF EXISTS tableD;' +
+				'CREATE TABLE tableC (id INT PRIMARY KEY);' +
+				'CREATE TABLE tableD (id INT, c_id INT FOREIGN KEY REFERENCES tableC(id));' +
+				'INSERT INTO tableC VALUES (10);' +
+				'INSERT INTO tableC VALUES (20);' +
+				'INSERT INTO tableD VALUES (1, 10);'
+		);
+
+		// This should fail with a proper error message
+		try {
+			alasql('INSERT INTO tableD VALUES (2, 99)');
+			assert.fail('Should have thrown an error for foreign key violation');
+		} catch (err) {
+			console.log('Error message:', err.message);
+			assert(err.message.includes('Foreign key'), 'Error should mention foreign key');
+			assert(err.message.includes('99'), 'Error should include the key value');
+			assert(err.message.includes('tableC'), 'Error should include the table name');
+			assert(!err.message.includes('undefined'), 'Error should not contain undefined');
+		}
+	});
+
+	it('C) Composite foreign key - error message should include table and keys', function () {
+		alasql(
+			'DROP TABLE IF EXISTS tableE;' +
+				'DROP TABLE IF EXISTS tableF;' +
+				'CREATE TABLE tableE (id1 INT, id2 INT, PRIMARY KEY (id1, id2));' +
+				'CREATE TABLE tableF (id INT, e_id1 INT, e_id2 INT, FOREIGN KEY (e_id1, e_id2) REFERENCES tableE(id1, id2));' +
+				'INSERT INTO tableE VALUES (1, 1);' +
+				'INSERT INTO tableE VALUES (2, 2);' +
+				'INSERT INTO tableF VALUES (1, 1, 1);'
+		);
+
+		// This should fail with a proper error message
+		try {
+			alasql('INSERT INTO tableF VALUES (2, 99, 99)');
+			assert.fail('Should have thrown an error for foreign key violation');
+		} catch (err) {
+			console.log('Error message:', err.message);
+			assert(err.message.includes('Foreign key'), 'Error should mention foreign key');
+			assert(err.message.includes('99'), 'Error should include the key value');
+			assert(err.message.includes('tableE'), 'Error should include the table name');
+			assert(!err.message.includes('undefined'), 'Error should not contain undefined');
+		}
+	});
+});