Question

使用ODBC将值绑定到类型DATETIME2(7)的存储过程参数的正确方法是什么。我想做点什么：

{CALL myproc (?,?)}

所以，我们假设第一个参数是一个int，第二个参数是DATETIME2。我能做到：

// Bind parameter 1, which is an INT
int val=5;
SQLLEN len=sizeof(val);
SQLBindParameter(hstmt, 1, SQL_PARAM_INPUT, SQL_C_SLONG, SQL_INTEGER, 4, 0, 
                 &val, sizeof(val), &len);

// Bind parameter 2, a DATETIME2(7) value
// How do I do this??? How do I store the DATETIME2(7) value so that it can be
// bound and is not a string or degenerate DATETIME type

感谢您的帮助！

Answer 1

首先让我说MSD中的ODBC datetime2交互是非常可靠的。经过反复试验，在MSDN上搜索（一直到SQL Server Denali CTP文档），无数的论坛等...，这里是正确绑定DATETIME2（7）参数的方法。 ODBC：

// This is a sample SQL_TIMESTAMP_STRUCT object, representing:
// 1987-06-05T12:34:45.1234567
// Notice the two zeroes at the end of the fractional part?
// These _must_ be zeroes, because the fractional part is in nanoseconds!
// If you put non-zeroes in this part, you _will_ get a binding error.
SQL_TIMESTAMP_STRUCT ts=
  {1987,6,5,12,34,45,123456700};

SQLRETURN result=::SQLBindParameter(hStmt, 
  2, // Parameter idx in my original question
  SQL_PARAM_INPUT,
  SQL_C_TIMESTAMP,
  SQL_TYPE_TIMESTAMP,
  // Next is the length of the _string_ repr. of the DATETIME2(7) type! WTF???
  // It should be 20 + {the value of the precision of the DATETIME2}
  // Remember that we are using: 1987-06-05T12:34:45.1234567 for this example
  27, 
  7, // This is the precision of the DATETIME2
  &ts,
  sizeof(ts),
  NULL);
if (result!=SQL_SUCCESS)
  ...

我希望这对下一个遭受ODBC和DATETIME2的愤怒的人有所帮助。

如何使用ODBC将值绑定到DATETIME2（7）类型的存储proc参数

1 个答案: