The first step in full text searching is to create a word list containing all the words in the database. Full text searching also has other features like stemming, which relates derived words to a base word (fast, faster, fastest) and it has stop words which are ignored because they are so common (and, the). A little VBA code can generate a word list which can be visually scanned. With a little more work, it would be possible to use code to check the word list first before searching the database and this might make searches much faster. Below is some code that I created for the purpose. Its real life application is to find peoples names in database so that I can remove or alter them for privacy protection and as a biologist, I want to italicize scientific names in reports. If I can create a list of scientific names, then I can replace them with the name enclosed in html tags.
The code works well but I have not tested it extensively or against large memo fields/rich text fields. It was written in Access 2010.
'This code requires a table called tblWordList with fields called Word (str 255), WordCount (long), FirstCopyID (long)
Option Compare Database
Option Explicit
'Click on this procedure and press F5 to run the code
Private Sub ScopeWordList()
'A list of tables and fields that need to be processed
Call CreateWordList("Issues", "IssueSummary", "IssueID")
End Sub
'The main routine that finds new words
Public Sub CreateWordList(TableName As String, FieldName As String, ForeignKey As String)
Dim dbs As Database
Dim rst As Recordset
Dim SQL_Statement As String
Dim r As Recordset
Dim RowText As String
Dim OriginalWord As String
Dim SearchWord As String
Dim SearchTerm As String
Dim Quote As String: Quote = Chr$(34)
Dim i As Long
Dim RecNum As Long
SQL_Statement = "SELECT " & FieldName & ", " & ForeignKey & " AS FirstCopyID FROM " & TableName & " WHERE " & FieldName & " IS NOT NULL;"
Set dbs = CurrentDb()
Set rst = dbs.OpenRecordset(SQL_Statement, dbOpenSnapshot)
Set r = dbs.OpenRecordset("tblWordCounts", dbOpenTable)
r.Index = "Word"
With rst
If .RecordCount = 0 Then GoTo ExitCreateWordList
Do Until .EOF
Dim RowWords As Variant 'holds an array which needs to be created
RowText = .Fields(0)
'strip out quotes, slashes and other characters
RowText = CleanLine(RowText)
'split data into words
RowWords = Split(RowText, Space(1))
For i = LBound(RowWords) To UBound(RowWords)
OriginalWord = RowWords(i)
SearchWord = Left(Trim(OriginalWord), 254)
If Len(SearchWord) > 0 Then
r.Seek "=", SearchWord
If r.NoMatch Then
r.AddNew
r!Word = SearchWord
r!wordcount = 1
'records ID field of first occurrence, so you can debug unexpected results
r!FirstCopyID = !FirstCopyID
r.Update
Else
r.Edit
r!wordcount = r!wordcount + 1
r.Update
End If
End If
' End If
Next i
RecNum = RecNum + 1
If RecNum Mod 20 = 0 Then Debug.Print "Record " & RecNum
.MoveNext
Loop
ExitCreateWordList:
End With
Debug.Print "Done"
Set rst = Nothing
Set dbs = Nothing
End Sub
'Need to clean out unwanted characters and replace then with normal spaces
Private Function CleanLine(RowText As String) As String
Dim X As Long
Dim Y As String
Dim Z As Long
Dim W As String
For X = 1 To Len(RowText)
Y = Mid(RowText, X, 1)
Z = Asc(Y)
Select Case Z
Case 65 To 90 'capital letters
W = W & Y
Case 97 To 122 'lowercase letters
W = W & Y
Case Else
W = W & Space(1)
End Select
Next
CleanLine = W
End Function
'Delete all records in Word List table
Public Sub ClearWordList()
Dim SQL_Statement As String
'Delete all records from tblWordCounts
SQL_Statement = "DELETE FROM tblWordCounts"
DoCmd.SetWarnings False
DoCmd.RunSQL SQL_Statement
DoCmd.SetWarnings True
End Sub