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srv_paramdata (Extended Stored Procedure API)

Important

This feature will be removed in a future version of Microsoft SQL Server. Do not use this feature in new development work, and modify applications that currently use this feature as soon as possible. Use CLR integration instead.

Returns the value of a remote stored procedure call parameter. This function has been superseded by the srv_paraminfo function.

Syntax


void * srv_paramdata (
SRV_PROC *
srvproc
,
int
n 
);

Arguments

  • srvproc
    Is a pointer to the SRV_PROC structure that is the handle for a particular client connection (in this case, the handle that received the remote stored procedure call). The structure contains information the Extended Stored Procedure library uses to manage communication and data between the application and the client.

  • n
    Is the number of the parameter. The first parameter is number 1.

Returns

A pointer to the parameter value. If the nth parameter is NULL, there is no nth parameter, or there is no remote stored procedure, returns NULL. If the parameter value is a string, it might not be null-terminated. Use srv_paramlen to determine the length of the string.

This function returns the following values, if the parameter is one of the Microsoft SQL Server data types. Pointer data includes whether the pointer for the data type is valid (VP), NULL, or not applicable (N/A), and the contents of the data pointed to.

New data types

Input data length

BITN

NULL: VP, NULL

ZERO: VP, NULL

>=255: N/A

<255: N/A

BIGVARCHAR

NULL: NULL, N/A

ZERO: VP, NULL

>=255: VP, 255 chars

<255: VP, actual data

BIGCHAR

NULL: NULL, N/A

ZERO: VP, 255 spaces

>=255: VP, 255 chars

<255: VP, actual data + padding (up to 255)

BIGBINARY

NULL: NULL, N/A

ZERO: VP, 255 0x00

>=255: VP, 255 bytes

<255: VP, actual data + padding (up to 255)

BIGVARBINARY

NULL: NULL, N/A

ZERO: VP, 0x00

>=255: VP, 255 bytes

<255: VP, actual data

NCHAR

NULL: NULL, N/A

ZERO: VP, 255 spaces

>=255: VP, 255 chars

<255: VP, actual data + padding (up to 255)

NVARCHAR

NULL: NULL, N/A

ZERO: VP, NULL

>=255: VP, 255 chars

<255: VP, actual data

NTEXT

NULL: N/A

ZERO: N/A

>=255: N/A

<255: N/A

*   data is not null-terminated; no warning is issued on truncation for data >255 characters.

Remarks

If you know the parameter name, you can use srv_paramnumber to get the parameter number. To determine whether a parameter is NULL, use srv_paramlen.

When a remote stored procedure call is made with parameters, the parameters can be passed by name or by position (unnamed). If the remote stored procedure call is made with some parameters passed by name and some passed by position, an error occurs. If an error occurs, the SRV_RPC handler is still called, but it appears as if there were no parameters and srv_rpcparams returns 0.

Security noteSecurity Note

You should thoroughly review the source code of extended stored procedures, and you should test the compiled DLLs before you install them on a production server. For information about security review and testing, see this Microsoft Web site.