VBExpert
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Avoid illegal chars in constructed SQL statements
So we go ahead and do one of those
MySQL="Update whatever"
MySQL=MySQL & "values (something)"
docmd.execute.MySQL
And run/test it and plop get an error. Upon checking you see the user typed something like a single quote mark in one of the string fields and aaha!
Now we filter for that and later PLOP
and PLOP so exactly where can we find a good routine for cleaning up these constructed SQL statements to prevent illegal characters? In fact we may wish to just permit a very selective group of characters except for a few special characters mostly alpha num space are all we mostly want going into these fields when we are updating.
Thanks in advance for your contributions!
MySQL="Update whatever"
MySQL=MySQL & "values (something)"
docmd.execute.MySQL
And run/test it and plop get an error. Upon checking you see the user typed something like a single quote mark in one of the string fields and aaha!
Now we filter for that and later PLOP
and PLOP so exactly where can we find a good routine for cleaning up these constructed SQL statements to prevent illegal characters? In fact we may wish to just permit a very selective group of characters except for a few special characters mostly alpha num space are all we mostly want going into these fields when we are updating.
Thanks in advance for your contributions!
Two things you might want to look at:
BuildCriteria method - This allows you access to the parsing code that is in the query grid. Would help you get better formatting in SQL statements.
English Wizard - an OCX control that takes english statements and translates them into SQL.
Jim.
BuildCriteria method - This allows you access to the parsing code that is in the query grid. Would help you get better formatting in SQL statements.
English Wizard - an OCX control that takes english statements and translates them into SQL.
Jim.
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Gee, the code looks quite difficult to read in this font!
It will make much more sense when you drop it into Access and use the code.
It will make much more sense when you drop it into Access and use the code.
I like nunga's suggestion, to build the string and then scrub it. That may be your best bet if you've already got tables full of data.
But I think the better solution lies in controlling the user's input. It is easy to control a user's input into a text box by comparing the keycode to an 'approved' list as they press each key.
I always prefer to clean data on the way in, rather than after afterwards.
Wes
But I think the better solution lies in controlling the user's input. It is easy to control a user's input into a text box by comparing the keycode to an 'approved' list as they press each key.
I always prefer to clean data on the way in, rather than after afterwards.
Wes
ASKER
I like the code in the remove characters module nunga but the ideal is probably going to be more like what JDettman has suggested.
I can't decide which way to go, and may keep working a bit longer on the solution unless you have a better list somewhere of characters which are always going to be rejected in SQL so we can improve on simply trying to fix " and ' instances.
Always changing "" to " or whatever I think still assumes too much and can still easily leave you with an invaloid SQL statement.
I can't decide which way to go, and may keep working a bit longer on the solution unless you have a better list somewhere of characters which are always going to be rejected in SQL so we can improve on simply trying to fix " and ' instances.
Always changing "" to " or whatever I think still assumes too much and can still easily leave you with an invaloid SQL statement.
Hi all.
The String Editor add-in, included in Office 2000 developer, greatly simplifies the process of formatting complex strings such as SQL statements or scripts. Using the String Editor, you can simply enter your string as stright text, then mark any string variables within the string. On complition, the String Editor will automatically format the string for you, inserting all of the necessary quotes and other formatting characters.
Cheers,
Dedushka
The String Editor add-in, included in Office 2000 developer, greatly simplifies the process of formatting complex strings such as SQL statements or scripts. Using the String Editor, you can simply enter your string as stright text, then mark any string variables within the string. On complition, the String Editor will automatically format the string for you, inserting all of the necessary quotes and other formatting characters.
Cheers,
Dedushka
ASKER
Dedushka I like your solution best although scrubbing strings was pretty good too this sounds more like what I was hoping for. If you can please provide some code to demonstrate the use of this String Editor Add-In I will award you the points?
ASKER
ok well lacking any suppoorting code or help I'll go ahead and give it to Nunga for the best effort.
Thanks everyone!
Thanks everyone!
You can scan for characters of a certain type, and set the string up accordingly. But what is allowed differs, depending on the task at hand.
If you use all double quotes in your strings, the single quotes should fly OK.
A pair of double quotes in a string places an individual doubble quote into the results:
Debug.Print "Today is ""Thursday"", you know."
will produce:
Today is "Thursday", you know.
You can look for quotes in the source of your string, and double them up in the code that does the concatenating.
Many write SQL code like the following, (I add a space between every character for clarity...)
s t r S Q L = s t r S Q L & " L I K E ' " & M e ! t x t B o x & " ' "
If you use the fol. instead
s t r S Q L = s t r S Q L & " L I K E " " " & M e ! t x t B o x & " " " "
a string from the text box with a single quote in it will cause no problems...
The problem you bring up is a thorny one, no doubt about it.
Brian