SQL Server 2019

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CREATE TABLE #TempLoaderTable (
        txtField nvarchar(100), 
        [Lat] nvarchar(25), 
        [Lon] nvarchar(25), 
        [Bearing] nvarchar(25), 
        [Distance] nvarchar(25)
        )

INSERT INTO #TempLoaderTable (txtField) 
    VALUES ('abcde,fghij,12345,6789')

SELECT * FROM #TempLoaderTable


txtField
Lat
Lon
Bearing
Distance


abcde,fghij,12345,6789
null
null
null
null


UPDATE  #TempLoaderTable
   SET  [Lat] = LEFT(txtField, CHARINDEX(',', txtField) - 1),
		[txtField] = STUFF(txtfield,1,CHARINDEX(',', txtField),'') 
   FROM #TempLoaderTable

SELECT * FROM #TempLoaderTable


txtField
Lat
Lon
Bearing
Distance


fghij,12345,6789
abcde
null
null
null


UPDATE  #TempLoaderTable
   SET  [Lon] = LEFT(txtField, CHARINDEX(',', txtField) - 1),
		[txtField] = STUFF(txtfield,1,CHARINDEX(',', txtField),'') 
   FROM #TempLoaderTable

SELECT * FROM #TempLoaderTable


txtField
Lat
Lon
Bearing
Distance


12345,6789
abcde
fghij
null
null


UPDATE  #TempLoaderTable
   SET  [Bearing] = LEFT(txtField, CHARINDEX(',', txtField) - 1),
		[txtField] = STUFF(txtfield,1,CHARINDEX(',', txtField),'') 
   FROM #TempLoaderTable

SELECT * FROM #TempLoaderTable


txtField
Lat
Lon
Bearing
Distance


6789
abcde
fghij
12345
null


UPDATE  #TempLoaderTable
   SET  [Distance] = [txtField],
		[txtField] = NULL
   FROM #TempLoaderTable

SELECT * FROM #TempLoaderTable


txtField
Lat
Lon
Bearing
Distance


null
abcde
fghij
12345
6789