Strange problem with string coming back from MySQL

[NateDog]

I don't know if this is a problem in the jdbc driver or in SFS but we can recreate it quite easily on our systems here.

The problem is the string.split() method not functioning properly for some "|" delimeted strings if the strings come back from the database.

Example Code:

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var testStr = "34|1|1|1|22|32|4|1|1|15|1|10|27|1|1|1|1|9|1|1|1|38";
var sql = "UPDATE error_test SET val = '" + testStr + "' WHERE id = 1";
	application.db.executeCommand(sql);
	
	var sql = "SELECT * FROM error_test WHERE id = 1";
	var q = application.db.executeQuery(sql);
	var tempRow = q.get(0);
	var tStr = tempRow.getItem("val");
	trace("Str:" + tStr);
	var t = tStr.split("|");
	trace("length:" + t.length);

To run this code, make a database table called error_test with a primary key column "id" and a varchar(255) column "val"

insert 1 row with id=1

run the code snippet and note that the split function is returning an array of length 51 instead of the correct 22.

if you call the split function with a variable containing the same string it works. If you change the delimeter to anything other than "|" it works also.

unlucky for us, "|" is our standard delimeter

just in case it's in SFS and not jdbc drivers, thought I'd pass it along.

<edit>
forgot to mention we're using mySQL 5 and the beta 5.0 jdbc driver
</edit>

[Lapo]

I think that the String object you're getting is a java.lang.String not a native Actionscript String.

Try casting it to the correct type before you call the split() method.

Like this:

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var tStr = String( tempRow.getItem("val") );

[NateDog]

Interesting. Is it consistent with the datatype it's returning? In other words, are all varchar db columns coming back as java strings always?

I'm not totally sure but I believe this problem isn't happening in all of our queries. Is there a benefit to ever having this come back as a java string vs. an actionscript string? Seems to definitely leave a big door open for programming errors because it isn't at all expected that we would have to cast the sql results to String() on all of the columns before using them.

[Lapo]

All datatypes returned by a query are Java datatypes, and you usually don't need to care about it.

In the particular case of the split() method there's however a difference in the expected behaviour.

In case you are unsure about what data type you're dealing with you can use this simple technique:

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trace( typeof(myVar) )

If the variable is a java object you will get an "object"
So if you expected a number or string and you get an "object" you're dealing with a Java object

To know what kind of object it is, use this:

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trace("type: " + myVar.getClass().getName())

It should display "java.lang.String" in the case of a Java String

Casting all the datatypes coming from java into their relative AS versions behind the scenes could cause a performance hit, especially on large data sets etc... We will try to extend our documentation to better indicate when and where this Java/Actionscript ambiguities may occur