The ' (single quote or apostrophe) is a string delimiter. In MySQL the ` (backtick) is used to escape names that are also keywords. The MS products use [brackets] for the task. I believe the standard way to escape is with " (double quotes). MySQL supports this syntax, and I believe the MS products do too. MySQL also supports using " (double quotes) for string delimiters. I don't know about the MS products, but I'd be surprised if they didn't. I believe Access forces you to use " (double quote) rather than ' (single quote) when you're using the actual Access program, but if you're connecting via ODBC the restriction is not enforced. Finally, I don't believe MS products use the ` (backtick) for anything, but I could be wrong.
Assuming a table with the proper structure, this would be a legal statement in MySQL, illustrating both keyword escapes. SELECT `group`, SUM(age) AS "count" FROM myTable GROUP BY `group` In MS SQL, you' d use brackets like this, instead of backticks: SELECT [group], SUM(age) AS "count" FROM myTable GROUP BY [group] In both cases, the decision to use " (double quotes) for the "count" keyword was complete arbitrary, it could have used the backtick/bracket escapes just as well. Note that a table.column reference is two identifiers, not one, so you'd escape it like this: "table"."column", not like this "table.column". So to make your SQL as general as possible, use ' (single quote) for strings (which I haven't demonstrated anywhere), and " (double quote) for keyword escapes. If you do that, it'll run on either platform as far as I know. cheers, barneyb On Mon, 31 Jan 2005 21:38:19 -0600, Nick Baker <[EMAIL PROTECTED]> wrote: > What is the story with the characters ` and ' in SQL and the like ? I have > never been able to find anything that gives some reasoning behind the > logic. Seems like the ` is used a little differently in MS Access, MySQL > and MS SQL? While the ' seems to be used to denote text or string for data. > > Thanks, > -- Barney Boisvert [EMAIL PROTECTED] 360.319.6145 http://www.barneyb.com/ Got Gmail? I have 6 invites. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~| Logware (www.logware.us): a new and convenient web-based time tracking application. Start tracking and documenting hours spent on a project or with a client with Logware today. Try it for free with a 15 day trial account. http://www.houseoffusion.com/banners/view.cfm?bannerid=67 Message: http://www.houseoffusion.com/lists.cfm/link=i:4:192509 Archives: http://www.houseoffusion.com/cf_lists/threads.cfm/4 Subscription: http://www.houseoffusion.com/lists.cfm/link=s:4 Unsubscribe: http://www.houseoffusion.com/cf_lists/unsubscribe.cfm?user=89.70.4 Donations & Support: http://www.houseoffusion.com/tiny.cfm/54
