OpenAPI User Guide > OpenAPI User Guide > OpenAPI Function Reference > OpenAPI Functions > IIapi_getDescriptor() Function--Communicate Format of Return Data with IIapi_getColumns()
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IIapi_getDescriptor() Function--Communicate Format of Return Data with IIapi_getColumns()
The IIapi_getDescriptor() function retrieves information from the server about the format of the data being returned to the application. This information includes the number of columns in a row and the type, length, precision, and scale of each column. The actual values are returned with a subsequent call to IIapi_getColumns().
IIapi_getDescriptor() output remains valid until the query is ended with the IIapi_close() function.
This function has the following syntax:
II_VOID IIapi_getDescriptor (IIAPI_GETDESCRPARM *getDescrParm);
typedef struct _IIAPI_GETDESCRPARM
{
      IIAPI_GENPARM       gd_genParm;
      II_PTR              gd_stmtHandle;
      II_LONG             gd_descriptorCount;
      IIAPI_DESCRIPTOR   *gd_descriptor;
} IIAPI_GETDESCRPARM;
This function has the following parameters:
gd_genParm
Type: input and delayed output
Specifies the generic parameters. For a description, see Generic Parameters).
gd_stmtHandle
Type: input
Specifies the statement handle identifying the query or event handle identifying the database event.
gd_descriptorCount
Type: delayed output
Specifies the number of columns being returned. This parameter is 0 if there is no data that meets the criteria of the query.
gd_descriptor
Type: delayed output
Specifies an array of buffers. The number of buffers is equal to the gd_descriptorCount value. Each buffer contains the description of a column, including information about the data type, length, precision, and scale.
The memory for this parameter is managed by OpenAPI. For more information, see Output Parameters Allocated by OpenAPI).
Last modified date: 01/30/2023