System.Data.SqlClient.SqlCommand对象可以执行的T-SQL的局限性是什么？

BEGIN TRANSACTION
BEGIN TRY

    IF NOT EXISTS
    (
        SELECT * 
        FROM INFORMATION_SCHEMA.TABLES 
        WHERE TABLE_CATALOG = (SELECT DB_NAME())
        AND TABLE_NAME = \'SchemaVersion\'
    )
        BEGIN
            Print \'Migrating up...\'

            CREATE TABLE SchemaVersion (
                Id INT IDENTITY(1,1) NOT NULL,
                Version INT NOT NULL,
                CONSTRAINT PK_SchemaVersion PRIMARY KEY CLUSTERED (
                    Id ASC
                )
            )

            INSERT INTO SchemaVersion (Version) VALUES(1)

            PRINT \'Migrated from 0 to 1\'
        END
    ELSE IF (SELECT Version FROM SchemaVersion) = 1
        BEGIN
            Print \'Migrating down...\'

            DROP TABLE Dia_SchemaVersion

            PRINT \'Migrated from 1 to 0\'
        END
     ELSE
        PRINT \'Not migrating...\'

    COMMIT TRANSACTION;

END TRY
BEGIN CATCH
    ROLLBACK TRANSACTION
END CATCH