Firebird 2.5 SQL错误代码= -104令牌未知

Question

尝试从Firebird数据库中选择数据时遇到问题，这是我的代码：

string SQLCash = "SELECT sum(t2.Cash-Change)" +
            "FROM dbFBHdr t1, dbFBCollection t2" +
            "WHERE t1.Branch = t2.Branch AND" +
            "t1.CashNo = t2.CashNo AND" +
            "t1.CashDate >= '08/10/2018 00:00:00' AND" +
            "t1.CashDate <= '08/10/2018 23:59:59' AND" +
            "t1.Status = 'CLOSED'";
FbCommand cmdCASH = new FbCommand(SQLCash, FbCon);
cmdCASH.ExecuteNonQuery();
FbDataReader readerCASH = cmdCASH.ExecuteReader();
while (readerCASH.Read() == true)
{
   PDC.CASH += (reader["Cash"].ToString());
}
this.txtCash.Text = PDC.CASH;

但是使用此代码，我遇到了一个错误，但是我不知道如何解决。
我将错误附在下面：

Answer 1

我在您的项目中运行了您的代码 这就是结果

"SELECT sum(t2.Cash-Change)FROM dbFBHdr t1, dbFBCollection t2WHERE t1.Branch = t2.Branch ANDt1.CashNo = t2.CashNo ANDt1.CashDate >= '08/10/2018 00:00:00' ANDt1.CashDate <= '08/10/2018 23:59:59' ANDt1.Status = 'CLOSED'"

您可以看到上面的代码在添加字符串之间缺少空格，可以在每个字符串的开头或结尾添加它。

另外，由于您正在使用多行，因此可以在字符串之前使用@，这将使您可以在一个字符串中包含多行，例如

string SQLCash = @"SELECT sum(t2.Cash-Change)
        FROM dbFBHdr t1, dbFBCollection t2
        WHERE t1.Branch = t2.Branch AND
        t1.CashNo = t2.CashNo AND
        t1.CashDate >= '08/10/2018 00:00:00' AND
        t1.CashDate <= '08/10/2018 23:59:59' AND
        t1.Status = 'CLOSED'";