databaselink - MySQL Connection Problem

I have a problem with the configuration of the J-Connector plug-in with a MySQL database. Most of the time all works well, but sometimes the connection remains blocked for 2 hours and then it gives this error:

JDBC::error: "Communications link failure\n\nThe last packet successfully
 received from the server was 7,200,110 milliseconds ago.  The last packet
 sent successfully to the server was 7,200,047 milliseconds ago."

Note: I'm executing the query right after the connection is set, without waiting. It seems that the query is fetching results (with Mathematica running), but instead it remains blocked for 2 hours and then it fails.

Edit: I have noticed that the connection is correctly estabilished, then during the execution of the query it magically disappears (I have seen this checking the SHOW PROCESSLIST with another connection to database), but the JDBC driver didn't know anything about this and then after 2 hours it gives the error.

It looks like it has a 2 hours timeout (7,200,000 milliseconds) which I didn't set, my question is: how can I set it to a more reasonable time (like 1 minute)? So I can catch the error and re-execute the query without waiting for a long time.

Or, anyway, do you have any other solution to handle MySQL connection problems?

Comments

functions - Get leading series expansion term?

Given a function f[x] , I would like to have a function leadingSeries that returns just the leading term in the series around x=0 . For example: leadingSeries[(1/x + 2)/(4 + 1/x^2 + x)] x and leadingSeries[(1/x + 2 + (1 - 1/x^3)/4)/(4 + x)] -(1/(16 x^3)) Is there such a function in Mathematica? Or maybe one can implement it efficiently? EDIT I finally went with the following implementation, based on Carl Woll 's answer: lds[ex_,x_]:=( (ex/.x->(x+O[x]^2))/.SeriesData[U_,Z_,L_List,Mi_,Ma_,De_]:>SeriesData[U,Z,{L[[1]]},Mi,Mi+1,De]//Quiet//Normal) The advantage is, that this one also properly works with functions whose leading term is a constant: lds[Exp[x],x] 1 Answer Update 1 Updated to eliminate SeriesData and to not return additional terms Perhaps you could use: leadingSeries[expr_, x_] := Normal[expr /. x->(x+O[x]^2) /. a_List :> Take[a, 1]] Then for your examples: leadingSeries[(1/x + 2)/(4 + 1/x^2 + x), x] leadingSeries[Exp[x], x] leadingSeries[(1/x + 2 + (1 - 1/x...

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How to remap graph properties?

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