Ansi рекомендует "ваш алиас", все возможные способы в SQL server
https://github.com/ktaranov/sqlserver-kit/blob/master/SQL%20Server%20Name%20Convention%20and%20T-SQL%20Programming%20Style.md /* Recommended due to ANSI */
SELECT SCHEMA_NAME(schema_id) + '.' + "name" AS "Tables" FROM sys.tables;
/* Not recommended but possible */
SELECT SCHEMA_NAME(schema_id) + '.' + [name] AS "Tables" FROM sys.tables;
SELECT Tables = SCHEMA_NAME(schema_id) + '.' + [name] FROM sys.tables;
SELECT "Tables" = SCHEMA_NAME(schema_id) + '.' + [name] FROM sys.tables;
SELECT [Tables] = SCHEMA_NAME(schema_id) + '.' + [name] FROM sys.tables;
SELECT 'Tables' = SCHEMA_NAME(schema_id) + '.' + [name] FROM sys.tables;
SELECT SCHEMA_NAME(schema_id) + '.' + [name] [Tables] FROM sys.tables;
SELECT SCHEMA_NAME(schema_id) + '.' + [name] 'Tables' FROM sys.tables;
SELECT SCHEMA_NAME(schema_id) + '.' + [name] "Tables" FROM sys.tables;
SELECT SCHEMA_NAME(schema_id) + '.' + [name] Tables FROM sys.tables;
SELECT SCHEMA_NAME(schema_id) + '.' + [name] AS [Tables] FROM sys.tables;
SELECT SCHEMA_NAME(schema_id) + '.' + [name] AS 'Tables' FROM sys.tables;
SELECT SCHEMA_NAME(schema_id) + '.' + [name] AS Tables FROM sys.tables;