Dim L As Variant
Dim conn As Object
Dim comm As Object
L =  25 
Set conn = CreateObject( "ADODB.Connection" )
conn.Open  "Provider=SQLOLEDB.1 ;Persist Security Info=False;User ID=sa;Password=password;" & _
 "Initial Catalog=DatabaseName;Data Source=ServerName" 
Set comm = CreateObject( "ADODB.Command" )
comm.ActiveConnection = conn
comm.CommandText =  "SELECT TOP 1  id, belki, zhiri, uglevodi, ABS(" & L & _
 "- (belki+zhiri+uglevodi)/3 ) AS mat_middle INTO Result FROM workTable ORDER BY mat_middle"
comm.Execute
Set comm = Nothing
conn.Close
Set conn = Nothing

Type Record
   Tovar As String *  20 
   Belki As Single
   Zhiri As Single
   Uglevodi As Single
End Type
Dim CustRec As Record, ResRec As Record
Dim L As Single, Min As Single, Tmp  As Single
Dim I As Integer, N As Integer, NumFile As Integer

Sub Test1()
L =  50 
N =  25 
NumFile = FREEFILE
OPEN  "c:\temp\worktabl.dat"  FOR RANDOM AS NumFile LEN = LEN(CustRec)
FOR i =  1  TO N
   READ CustRec.Tovar, CustRec.Belki, CustRec.Zhiri, CustRec.Uglevodi
   PUT NumFile, i, CustRec
NEXT
CLOSE NumFile
DATA  "Tovar 1 ", 100 , 100 , 100 
...
DATA  "Tovar 25 ", 200 , 200 , 200 
'NumFile = FreeFile
'Open  "c:\temp\worktabl.dat"  For Random As NumFile Len = Len(CustRec)
'Randomize Timer
'For I =  1  To N
'   CustRec.Tovar = "Tovar" + Str$(I)
'   CustRec.Belki =  1000  * Rnd
'   CustRec.Zhiri = 1000 * Rnd
'   CustRec.Uglevodi =  1000  * Rnd
'   Put NumFile, I, CustRec
'Next
'Close NumFile
'Call Test2
End Sub

Sub Test2()
L =  50 
Min =  3 .4E+ 38 
NumFile = FreeFile
Open  "c:\temp\worktabl.dat"  For Random As NumFile Len = Len(CustRec)
N = Len(NumFile) / Len(CustRec)
For I =  1  To N
   Get NumFile, I, CustRec
   Tmp = Abs((CustRec.Belki + CustRec.Zhiri + CustRec.Uglevodi) /  3  - L)
   If Tmp < Min Then Min = Tmp: ResRec = CustRec
Next
Close NumFile
NumFile = FreeFile
Open  "c:\temp\Result.dat"  For Random As NumFile Len = Len(ResRec)
Put NumFile,  1 , ResRec
Close NumFile
End Sub

Min =  3 .4E+ 38 

Tmp = Abs((CustRec.Belki + CustRec.Zhiri + CustRec.Uglevodi) /  3  - L)

If Tmp < Min Then Min = Tmp : ResRec = CustRec