在我目前的项目中,我正在使用sql CE.由于它不支持存储过程,我必须在存储库中编写SQL查询.
选项1：
StringBuilder query = new StringBuilder();
query.Append("SELECT");
query.Append(" c.CUSTOMER_ID,");
query.Append(" COALESCE (c.FIRST_NAME,'') + ' ' + COALESCE (c.LAST_NAME,'') AS FULL_NAME");
query.Append(" ct.NAME as CUSTOMER_TYPE");
query.Append("FROM ");
query.Append(" CT_CUSTOMER_TYPE AS ct INNER JOIN CUSTOMER AS c ON ct.CUSTOMER_TYPE_ID = c.CUSTOMER_TYPE_ID");
选项2：
string query = "SELECT c.CUSTOMER_ID,COALESCE (c.FIRST_NAME,'') AS FULL_NAME,ct.NAME as CUSTOMER_TYPE FROM CT_CUSTOMER_TYPE AS ct INNER JOIN CUSTOMER AS c ON ct.CUSTOMER_TYPE_ID = c.CUSTOMER_TYPE_ID";
选项1似乎更具可读性,特别是当我有10个表连接时,但选项2更快.
我应该接受哪个选项,在这种情况下最佳做法是什么？
解决方法
选项2可能会快几纳秒,但是当您在数据库中添加实际执行的时间(几毫秒)时,几个额外的纳秒几乎不会记录为噪声.
在任何情况下,还有另一种选择,这是两个世界中最好的选择：@ -strings：
string query = @"
SELECT
c.CUSTOMER_ID,''_ + ' ' + COALESCE (c.LAST_NAME,'') AS FULL_NAME
ct.NAME as CUSTOMER_TYPE
FROM
CT_CUSTOMER_TYPE AS ct INNER JOIN CUSTOMER AS c
ON ct.CUSTOMER_TYPE_ID = c.CUSTOMER_TYPE_ID
";
