Function dpiStmt_defineValue 

pub unsafe extern "C" fn dpiStmt_defineValue(
    stmt: *mut dpiStmt,
    pos: u32,
    oracleTypeNum: dpiOracleTypeNum,
    nativeTypeNum: dpiNativeTypeNum,
    size: u32,
    sizeIsBytes: c_int,
    objType: *mut dpiObjectType,
) -> c_int

Defines the type of data that will be used to fetch rows from the statement. This is intended for use with the function dpiStmt_getQueryValue(), when the default data type derived from the column metadata needs to be overridden by the application. Internally, a variable is created with the specified data type and size.

The function returns DPI_SUCCESS for success and DPI_FAILURE for failure.