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4D v14.1

ODBC_SQLDrivers


ODBC_SQLDrivers ( direction ; driverDescription ; driverAttributes ) -> Function result

Parameter	Type	Description
direction	Longint	Direction from which to retrieve the drivers
driverDescription	Text	Description of the driver
driverAttributes	Text	List of driver attribute value pairs
Function result	Longint	Returns the result of the MS ODBC API function SQLDrivers

Description

The ODBC_SQLDrivers command lists driver descriptions and driver attribute keywords.

The direction parameter determines which driver in the Driver Manager list to retrieve and can be one of the following values:

Constant	Description
SQL_FETCH_NEXT	Fetch the next driver description in the list
SQL_FETCH_FIRST	Fetch from the beginning of the driver description list

driverDescription is the description of the driver, such as "SQL Server", "Microsoft Access Driver (*.mdb)", and "Microsoft ODBC for Oracle".

driverAttributes returns the list of driver attribute pairs, such as "UsageCount", "SQLLevel", "FileUsage", "DirverODBCVer", "ConnectFunctions", "APILevel", "CPTimeout", and "FileExtns" along with their values, such as "UsageCount=2" and each pair is delimited by a Char(0).

For more information, please see the SQLDrivers function in the MS ODBC API Reference at http://msdn.microsoft.com/en-us/library/ms712400(VS.85).aspx.

Function Results

SQL_SUCCESS, SQL_SUCCESS_WITH_INFO, SQL_NO_DATA, SQL_ERROR, or SQL_INVALID_HANDLE.

Example

The following method puts the driver description in one array and the driver's attribute value pairs into two-dimensional arrays:

 ARRAY TEXT(arDriverDesc;0)

 ARRAY TEXT(arAttrName;0;0) `Two-dimensional arrays to store the attribute pairs

 ARRAY TEXT(arAttrValue;0;0)

 $result:=ODBC_SQLDrivers(SQL_FETCH_FIRST;vDriverDesc;vDriverAttrPair)

 If($result=SQL_SUCCESS)

    Repeat

       APPEND TO ARRAY(arDriverDesc;vDriverDesc)

       $size:=Size of array(arDriverDesc)

       INSERT ELEMENT(arAttrName;$size)

       INSERT ELEMENT(arAttrValue;$size)

       ParseDriverAttributePairs(vDriverAttrPair;->arAttrName{$size};->arAttrValue{$size})

       $result:=ODBC_SQLDrivers(SQL_FETCH_NEXT;vDriverDesc;vDriverAttrPair)

    Until($result=SQL_NO_DATA)

 End if

Here is the code for the ParseDriverAttributePairs method:

  ` Method: ParseDriverAttributePairs

  ` $1 : Text : Input text to parse

  ` $2 : Pointer : A text array to hold the names

  ` $3 : Pointer : A text array to hold the values

 

 C_TEXT($1;$input_t;$valuePair_t)

 C_POINTER($2;$3;$names_aptr;$values_aptr)

 C_LONGINT($position_i)

 $input_t:=$1

 $names_aptr:=$2

 $values_aptr:=$3

 ARRAY TEXT($names_aptr->;0)

 ARRAY TEXT($values_aptr->;0)

 Repeat

    $position_i:=Position(Char(0);$input_t)

    If($position_i>0)

       $valuePair_t:=Substring($input_t;1;$position_i)

       $input_t:=Substring($input_t;$position_i+1)

       $position_i:=Position("=";$valuePair_t)

       If($position_i>0)

          APPEND TO ARRAY($names_aptr->;Substring($valuePair_t;1;$position_i-1))

          APPEND TO ARRAY($values_aptr->;Substring($valuePair_t;$position_i+1))

       End if

    End if

 Until($position_i=0)