if(!session.hasBegun()) begin() … if (!wasBegun) commit
John Abraham <[email protected]> Tue, 6 Mar 2012 15:16:49 -0700
| Newsgroups | gmane.comp.java.orm.simpleorm |
|---|---|
| Message-ID | <[email protected]> |
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I have a system (calibrating a scientific simulation) that generally hits t=
he database early and grabs all the data it needs in the first 5 minutes. =
It's been keeping the connection to the database open "Idle In Transaction"=
, which is a problem for the database since it runs for days and weeks.=20
A lot of the data never gets changed, so I've identified these and I've det=
ached a few datasets full of static data so I can query them at will and ju=
st toss them later.=20=20
But some data does get changed, and there is always a chance that some data=
might not get queried until much later in the simulation. So I think I ne=
ed to keep a connection open, just commit it after the initial burst of que=
ries, then <begin=85. commit> for any later queries that occur.
What's the best practice for begin.. commit wrapping like this?
I was thinking of wrapping a lot of my stuff in
boolean wasBegun =3D true;
if (!session.hasBegun()) {
session.begin();
wasBegun=3Dfalse;
}
=85 do my query and stuff=85.
if (!wasBegun) session.commit();
This way I can use a big begin() commit() wrap for the all the initial quer=
ies, then rely on smaller begin() commit() wraps for the stuff that occurs =
randomly later on.
What do you think of this plan? Is there a better system?
--
John Abraham
[email protected]
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I have a system (calibrating a scientific simulation) that generally hits t=
he database early and grabs all the data it needs in the first 5 minutes. &=
nbsp;It's been keeping the connection to the database open "Idle In Transac=
tion", which is a problem for the database since it runs for days and weeks=
. <div><br></div><div>A lot of the data never gets changed, so I've id=
entified these and I've detached a few datasets full of static data so I ca=
n query them at will and just toss them later. </div><div><br></div><=
div>But some data does get changed, and there is always a chance that some =
data might not get queried until much later in the simulation. So I t=
hink I need to keep a connection open, just commit it after the initial bur=
st of queries, then <begin=85. commit> for any later queries that occ=
ur.</div><div><br></div><div>What's the best practice for begin.. commit wr=
apping like this?</div><div><br></div><div>I was thinking of wrapping a lot=
of my stuff in</div><div><br></div><div><font class=3D"Apple-style-span" f=
ace=3D"'Courier New'">boolean wasBegun =3D true;</font></div><div><font cla=
ss=3D"Apple-style-span" face=3D"'Courier New'">if (!session.hasBegun()) {</=
font></div><div><font class=3D"Apple-style-span" face=3D"'Courier New'">&nb=
sp; session.begin();</font></div><div><font class=3D"Apple-style-span=
" face=3D"'Courier New'"> wasBegun=3Dfalse;</font></div><div><f=
ont class=3D"Apple-style-span" face=3D"'Courier New'">}</font></div><div><f=
ont class=3D"Apple-style-span" face=3D"'Courier New'"><br></font></div><div=
><font class=3D"Apple-style-span" face=3D"'Courier New'">=85 do my query an=
d stuff=85.</font></div><div><font class=3D"Apple-style-span" face=3D"'Cour=
ier New'"><br></font></div><div><font class=3D"Apple-style-span" face=3D"'C=
ourier New'">if (!wasBegun) session.commit();</font></div><div><br></div><d=
iv><br></div><div>This way I can use a big begin() commit() wrap for the al=
l the initial queries, then rely on smaller begin() commit() wraps for the =
stuff that occurs randomly later on.</div><div><br></div><div>What do you t=
hink of this plan? Is there a better system?</div><div><br></div><div=
>--</div><div>John Abraham</div><div><a href=3D"mailto:[email protected]">j=
[email protected]</a></div>
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