fix(mssql): columnInfo() now works with case-sensitive database [fixes #4573]

lib/dialects/mssql/query/mssql-querycompiler.js

@@ -429,7 +429,8 @@ class QueryCompiler_MSSQL extends QueryCompiler {
       schema = this.client.customWrapIdentifier(schema, identity);
     }
 
-    let sql = `select [COLUMN_NAME], [COLUMN_DEFAULT], [DATA_TYPE], [CHARACTER_MAXIMUM_LENGTH], [IS_NULLABLE] from information_schema.columns where table_name = ? and table_catalog = ?`;
+    // GOTCHA: INFORMATION_SCHEMA.COLUMNS must be capitalized to work when the database has a case-sensitive collation. [#4573]
+    let sql = `select [COLUMN_NAME], [COLUMN_DEFAULT], [DATA_TYPE], [CHARACTER_MAXIMUM_LENGTH], [IS_NULLABLE] from INFORMATION_SCHEMA.COLUMNS where table_name = ? and table_catalog = ?`;
     const bindings = [table, this.client.database()];
 
     if (schema) {

test/integration/query/additional.js

@@ -300,7 +300,7 @@ module.exports = function (knex) {
         [drivers.SQLite]: "SELECT name FROM sqlite_master WHERE type='table';",
         [drivers.Oracle]: 'select TABLE_NAME from USER_TABLES',
         [drivers.MsSQL]:
-          "SELECT table_name FROM information_schema.tables WHERE table_schema='dbo'",
+          "SELECT table_name FROM INFORMATION_SCHEMA.TABLES WHERE table_schema='dbo'",
       };
       return knex
         .raw(tables[knex.client.driverName])
@@ -417,7 +417,7 @@ module.exports = function (knex) {
           );
           tester(
             'mssql',
-            "select [COLUMN_NAME], [COLUMN_DEFAULT], [DATA_TYPE], [CHARACTER_MAXIMUM_LENGTH], [IS_NULLABLE] from information_schema.columns where table_name = ? and table_catalog = ? and table_schema = 'dbo'",
+            "select [COLUMN_NAME], [COLUMN_DEFAULT], [DATA_TYPE], [CHARACTER_MAXIMUM_LENGTH], [IS_NULLABLE] from INFORMATION_SCHEMA.COLUMNS where table_name = ? and table_catalog = ? and table_schema = 'dbo'",
             ['datatype_test', 'knex_test'],
             {
               enum_value: {
@@ -493,7 +493,7 @@ module.exports = function (knex) {
           );
           tester(
             'mssql',
-            "select [COLUMN_NAME], [COLUMN_DEFAULT], [DATA_TYPE], [CHARACTER_MAXIMUM_LENGTH], [IS_NULLABLE] from information_schema.columns where table_name = ? and table_catalog = ? and table_schema = 'dbo'",
+            "select [COLUMN_NAME], [COLUMN_DEFAULT], [DATA_TYPE], [CHARACTER_MAXIMUM_LENGTH], [IS_NULLABLE] from INFORMATION_SCHEMA.COLUMNS where table_name = ? and table_catalog = ? and table_schema = 'dbo'",
             null,
             {
               defaultValue: null,

test/integration/schema/index.js

@@ -1463,6 +1463,49 @@ module.exports = (knex) => {
             .then(() =>
               knex.schema.withSchema(testSchemaName).dropTableIfExists('test2')
             ));
+
+        describe('case-sensitive collation support', () => {
+          let k;
+          const databaseName = 'knex_test_CS_AS_SC';
+          const collation = 'Latin1_General_100_CS_AS_SC';
+          const tableName = 'Test';
+          before(async () => {
+            await knex.schema.raw(
+              `IF EXISTS(SELECT name FROM sys.databases WHERE name = :databaseName) DROP DATABASE :databaseName:; CREATE DATABASE :databaseName: COLLATE ${collation}`,
+              { databaseName }
+            );
+
+            const Knex = require('../../../knex');
+            const config = require('../../knexfile');
+            k = Knex({
+              client: 'mssql',
+              connection: {
+                ...config.mssql.connection,
+                database: databaseName,
+              },
+            });
+
+            // Verify configuration is using the correct database.
+            const [{ name }] = await k.raw('SELECT DB_NAME() AS name');
+            expect(name).to.equal(databaseName);
+
+            await k.schema.createTable(tableName, function () {
+              this.increments();
+            });
+          });
+          after(async () => {
+            await k.schema.dropTable(tableName);
+            await k.destroy();
+            await knex.schema.raw(
+              `IF EXISTS(SELECT name FROM sys.databases WHERE name = :databaseName) DROP DATABASE :databaseName:`,
+              { databaseName }
+            );
+          });
+          it('should get columnInfo from a case-sensitive database', async () => {
+            const info = await k(tableName).columnInfo();
+            expect(info).not.to.equal(undefined);
+          });
+        });
       });
     });