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Posted: **Thu Sep 25, 2014 10:35 pm**

Hi,

I tried updating the command bookupdate to have placeholders to help with have special characters in the data... if I entered in a book with a title that has a quote - I can't update that book unless I take the quote out. I modified these lines

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   ## Construct the SQL statement and execute it on the database
  put "UPDATE books SET status='" & pStatus & "', title='" & pTitle & "',author='" & pAuthor & "',comments='" & pComments &"' WHERE BookID = '" & pBookID & "'" into tSQLStatement
revExecuteSQL sDatabaseID,tSQLStatement

And replaced it with this code...

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   put "UPDATE books SET status = :1, title = :2, author = :3, comments = :4 WHERE BookID = :5" into tSQLStatement
   revExecuteSQL sDatabaseID, tSQLStatement,  "pStatus","pTitle","pAuthor","pComments","pBookID"

It says the book was updated but the change never occurs - when I revert to the original code it works, I am making some kind of obvious error?

Thanks,
Ripper

Posted: **Fri Sep 26, 2014 8:29 am**

Special characters... need special treatment.

For instance, single quote have to be replaced with \'

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replace "'" with "\'" in tString

If you try to do a SQL update or insert with a string that contains a single quote, it wont work, because single quotes are used as delimiter by SQL.

Same for CR (carriage return) etc. A string with a CR inside, can create problem when you do a revDataFromQuery with CR delimiter (for records).

2 fixes :

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replace CR with "\n" in tString

or
change the standard delimiter with revDataFromQuery

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put revDataFromQuery (tab,"|",dbID,dbSQL) into tData
replace "|" with CR in tData

Posted: **Fri Sep 26, 2014 2:09 pm**

Thanks for the info... I will try it.

According to the documentation below for revExecuteSQL - is there something wrong with my updated command in the original post... it's not updating even when I'm not using quotes in the title...

This is the part I'm talking about..

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Comments:
The SQLStatement may contain one or more placeholders, which are sequential numbers prepended by a colon. The revExecuteSQL command substitutes the corresponding item in the variablesList for each of these placeholders. For example, if you have two variables called "valueX" and "valueY", you can use a SQLStatement that includes placeholders as follows:

revExecuteSQL myID, "insert into mytable values(:1,:2,:1)", "valueX","valueY"

The content of the variable valueX is substituted for the ":1" in the SQLQuery (in both places where ":1" appears), and the content of valueY is substituted for ":2".

Thanks,
Ripper

Posted: **Fri Sep 26, 2014 4:10 pm**

One advice : before to use "variable list", start with the regular form

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put "update mytable set valueX=1 where valueX=0" into tSQL
answer tSQL
revExecuteSQL myID,tSQL
put the result into tResult
answer tResult

or

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put "insert into mytable (valueX,valueY) values ('1','2')" into tSQL
answer tSQL
revExecuteSQL myID,tSQL
put the result into tResult
answer tResult

-it's easier to read
-it allows you to know exactly what you send to the SQL server for easier debuging

Posted: **Fri Sep 26, 2014 4:38 pm**

Thanks for the info - I've tried that and it looks good. But I can't tell if the placeholder values are actually being replaced.. has anyone tried my example in 7.0 rc2?

Thanks,
Ripper

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Book Library - revExecuteSQL in 7.0 (rc 2)

Book Library - revExecuteSQL in 7.0 (rc 2)

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Re: Book Library - revExecuteSQL in 7.0 (rc 2)

Re: Book Library - revExecuteSQL in 7.0 (rc 2)

Re: Book Library - revExecuteSQL in 7.0 (rc 2)