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Optimistic vs. Pessimistic locking
...stay unmodified for the duration, it's as accurate as pessimistic locking (select for update style) on those same records. The main difference is that optimistic locking incurs overhead only if there's a conflict, whereas pessimistic locking has reduced overhead on conflict. So optimistic is best ...
How can a LEFT OUTER JOIN return more records than exist in the left table?
...FT table, then you have no need to perform a JOIN at all and can just do a SELECT directly from the LEFT table.
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missing private key in the distribution certificate on keychain
...ain Access application to export both the certificate and the private key. Select both using shift or command and right click to export to a .p12 file.
Attached a screenshot to make it very clear.
On your mac, import that .p12 file and you are good to go (just make sure you have a valid provisioni...
EC2 Instance Cloning
...he easier way is through the web management console:
go to the instance
select the instance and click on instance action
create image
Once you have an image you can launch another cloned instance, data and all. :)
shar...
How to use a WSDL
... the project and pick Connected Service from the Add context menu.
I would select Microsoft WCF Web Service Reference Provider from the list.
I would press browse and select the wsdl file straight away, Set the namespace and I am good to go.
Refer to the error fix url above if you encounter any err...
Multi flavor app based on multi flavor library in Android Gradle
...ile project(path: ':lib', configuration: 'market2Release')
}
Now you can select the app flavor and Build Variants panel and the library will be selected accordingly and all build and run will be done based on the selected flavor.
If you have multiple app module based on the library Android Studio...
Count, size, length…too many choices in Ruby?
...e will generate a query that requests all of the items from the database ('select * from mytable') and then give you the number of items resulting, whereas .count will generate a single query ('select count(*) from mytable') which is considerably faster.
Because these ORMs are so prevalent I follow...
Storing Data in MySQL as JSON
... statement, including WHERE, ORDER BY, and GROUP BY clauses. This includes SELECT, UPDATE, DELETE, CREATE TABLE, and other SQL statements. The left hand side must be a JSON column identifier (and not an alias). The right hand side is a quoted JSON path expression which is evaluated against the JSON ...
Visual Studio retrieving an incorrect path to a project from somewhere
...Source Control menu or the workspace drop down in Source Control Explorer)
select edit for your workspace.
You should see, under working folders, a mapping for the source
control directory to the old/wrong project directory.
Select it and click remove.
Close VS and delete the suo file.
It still r...
PDO MySQL: Use PDO::ATTR_EMULATE_PREPARES or not?
... I'm using caches on multiple levels anyway. You can always explicitly use SELECT SQL_CACHE <rest of statement> though.
– Will Morgan
May 4 '12 at 16:37
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