Sorry, put that "var c = null;" outside the function, and maybe give it a less
likely to be messed with name like var __persistentDBConnection = null;
-Matt
On Apr 8, 2012, at 9:24 PM, Matt Patenaude wrote:
> In that case, you might consider doing something like this:
>
> function obtainConnection(callback){
> var c = null;
> if (c == null){
> var conn = db.open(... fn() {
> c = conn;
> callback(c);
>
> // set some close timeout here
> });
> }
> else
> callback(c);
> }
>
> function dbQuery(query, callback){
> obtainConnection(fn() {
> db.collection(... fn() {
> db.query(query, callback);
> });
> });
> }
>
> Voila! Connection reuse. :)
>
> -Matt
>
> On Apr 8, 2012, at 9:17 PM, Matthew Hazlett wrote:
>
>> Thats how I originally did it, but when you need to do multiple queries to
>> the database you shoud open the connection once and reuse it instead of
>> opening it multiple times a session.
>>
>>
>> On 4/8/2012 9:14 PM, Matt Patenaude wrote:
>>>
>>> I agree, it seems entirely manageable.
>>>
>>> One low-overhead option would be just to split that out into a function, if
>>> it's used frequently:
>>>
>>> function dbQuery(query, callback){
>>> db.open(... fn() {
>>> db.collection(.... fn() {
>>> db.query(query, callback);
>>> });
>>> });
>>> }
>>>
>>>
>>> dbQuery("SELET * FROM blah", fn() {
>>> // stuff you would have done in the inner-most part here
>>> });
>>>
>>>
>>> -Matt
>>>
>>> On Apr 8, 2012, at 9:06 PM, Mark Hahn wrote:
>>>
>>>> > But as you can see this creates callback hell.
>>>>
>>>> It doesn't look that bad to me.
>>>>
>>>>
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