unescaping strings with the C api
Using MySQL 5.0.45 on linux. For the first time I am using the C API directly. I am using mysql_real_escape_string() - see http://dev.mysql.com/doc/refman/5.1/en/mysql-real-escape-string.html I can not locate a C api function to _unescape_ strings. If there were one, I would use it. If I have overlooked something in the API, I would welcome comments. I am familiar with methods outside of the API for unescaping. Thanks Tim -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: unescaping strings with the C api
Tim Johnson wrote: I can not locate a C api function to _unescape_ strings. Why do you believe you need one? You need to escape strings when building SQL query strings to avoid problems with quote characters, which are special in SQL. When MySQL returns the queried data to your program, it's not using a SQL query to do so. It just gives the data back in a directly usable form. You'd only need an unescape function if you were writing a SQL parser. -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: unescaping strings with the C api
On Thursday 12 June 2008, Warren Young wrote: Tim Johnson wrote: I can not locate a C api function to _unescape_ strings. Why do you believe you need one? You need to escape strings when building SQL query strings to avoid problems with quote characters, which are special in SQL. When MySQL returns the queried data to your program, it's not using a SQL query to do so. It just gives the data back in a directly usable form. Not sure what you mean by directly usable. If I do an insert statement with a backslash, for example: headline\one, I will retrieve headline\\one, and that will need to be unescaped, because it is not a true representation of what was submitted by the original insert. tim -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: unescaping strings with the C api
Tim Johnson wrote: Not sure what you mean by directly usable. I mean directly usable. :) If I do an insert statement with a backslash, for example: headline\one, I will retrieve headline\\one, and that will need to be unescaped, because it is not a true representation of what was submitted by the original insert. My perspective is a little different from yours: as the maintainer of MySQL++ (http://tangentsoft.net/mysql++/), I have never actually used the C API directly. I don't have any pure C sample code here to tweak to try things. Instead, I changed one of the MySQL++ examples to insert a string with a backslash into the DB, and on retrieving the rows, I get a single backslash. In the C++ code, the backslash is doubled due to C/C++ string parsing rules, but that's only one character in the underlying string data. Due to the way this example uses MySQL++, that string gets automatically escaped on DB insertion, so I presume it's sent over the wire as two backslashes, though I haven't verified it. Then when you retrieve rows through MySQL++, it returns a fairly direct copy of the data the C API gives you, with no real translation going on. MySQL++ doesn't have an unescape function, so I don't see why your program would need one. -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: unescaping strings with the C api
On Thursday 12 June 2008, Warren Young wrote: Tim Johnson wrote: Not sure what you mean by directly usable. I mean directly usable. :) If I do an insert statement with a backslash, for example: headline\one, I will retrieve headline\\one, and that will need to be unescaped, because it is not a true representation of what was submitted by the original insert. My perspective is a little different from yours: as the maintainer of MySQL++ (http://tangentsoft.net/mysql++/), I have never actually used the C API directly. I don't have any pure C sample code here to tweak to try things. Me neither - not any more anyway, since I quit coding in C C++ years ago.. Furthermore, I am also working with a scripting language new to me. My experience is with python - where unescaping is _not_ an issue and rebol, where unescaping _is_ an issue. Python using the API (somewhere buried deep in the MySQLdb modules, and rebol using a direct socket connection on port 3306. Instead, I changed one of the MySQL++ examples to insert a string with a backslash into the DB, and on retrieving the rows, I get a single backslash. In the C++ code, the backslash is doubled due to C/C++ string parsing rules, but that's only one character in the underlying string data. Due to the way this example uses MySQL++, that string gets automatically escaped on DB insertion, so I presume it's sent over the wire as two backslashes, though I haven't verified it. Then when you retrieve rows through MySQL++, it returns a fairly direct copy of the data the C API gives you, with no real translation going on. I'm seeing the same that you are with the language (newlisp) that I am playing with. MySQL++ doesn't have an unescape function, so I don't see why your program would need one. I believe that you are correct. If not a single regex should handle it, and be fairly fast. Thanks for the input. I really appreciate it. Best regards tim(looking at MySQL++) -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: unescaping strings with the C api
On 6/12/08, Tim Johnson [EMAIL PROTECTED] wrote: On Thursday 12 June 2008, Warren Young wrote: Tim Johnson wrote: Not sure what you mean by directly usable. I mean directly usable. :) If I do an insert statement with a backslash, for example: headline\one, I will retrieve headline\\one, and that will need to be unescaped, because it is not a true representation of what was submitted by the original insert. My perspective is a little different from yours: as the maintainer of MySQL++ (http://tangentsoft.net/mysql++/), I have never actually used the C API directly. I don't have any pure C sample code here to tweak to try things. Me neither - not any more anyway, since I quit coding in C C++ years ago.. Furthermore, I am also working with a scripting language new to me. My experience is with python - where unescaping is _not_ an issue and rebol, where unescaping _is_ an issue. Python using the API (somewhere buried deep in the MySQLdb modules, and rebol using a direct socket connection on port 3306. Instead, I changed one of the MySQL++ examples to insert a string with a backslash into the DB, and on retrieving the rows, I get a single backslash. In the C++ code, the backslash is doubled due to C/C++ string parsing rules, but that's only one character in the underlying string data. Due to the way this example uses MySQL++, that string gets automatically escaped on DB insertion, so I presume it's sent over the wire as two backslashes, though I haven't verified it. Then when you retrieve rows through MySQL++, it returns a fairly direct copy of the data the C API gives you, with no real translation going on. I'm seeing the same that you are with the language (newlisp) that I am playing with. MySQL++ doesn't have an unescape function, so I don't see why your program would need one. I believe that you are correct. If not a single regex should handle it, and be fairly fast. Thanks for the input. I really appreciate it. Best regards tim(looking at MySQL++) The same is true of mysql_real_escape_string() in PHP. You escape special characters upon update or insertion, but upon viewing the data in the DB or retrieving it programmatically, the data simply appear as it was originally before use of the function. David -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
Re: unescaping strings with the C api
On Thursday 12 June 2008, David Giragosian wrote: The same is true of mysql_real_escape_string() in PHP. You escape special characters upon update or insertion, but upon viewing the data in the DB or retrieving it programmatically, the data simply appear as it was originally before use of the function. Yup. The API takes care of it all . definitely a case for using the API over TCP/IP tim -- MySQL General Mailing List For list archives: http://lists.mysql.com/mysql To unsubscribe:http://lists.mysql.com/[EMAIL PROTECTED]
