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MySQL check if a table exists without throwing an exception
...
If you're using MySQL 5.0 and later, you could try:
SELECT COUNT(*)
FROM information_schema.tables
WHERE table_schema = '[database name]'
AND table_name = '[table name]';
Any results indicate the table exists.
From: http://www.electrictoolbox.com/check-if-mysql-table-exis...
Java project in Eclipse: The type java.lang.Object cannot be resolved. It is indirectly referenced f
...teps could help:
Right-click on project » Properties » Java Build Path
Select Libraries tab
Find the JRE System Library and remove it
Click Add Library... button at right side » Add the JRE System Library (Workspace default JRE)
...
HTTP Error 403.14 - Forbidden - The Web server is configured to not list the contents of this direct
...d features" in Server Manager.
In Wizard scroll down to the Web server and select : Web Server -> Application Development. Select all except CGI from the list as shown in the screen shot
Finally hit next and Install.
Restart IIS
Your website may start working.
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jQuery OR Selector?
I am wondering if there is a way to have "OR" logic in jQuery selectors. For example, I know an element is either a descendant of an element with class classA or classB, and I want to do something like elem.parents('.classA or .classB') . Does jQuery provide such functionality?
...
How to access a mobile's camera from a web app?
...re="capture" (Boolean) . The attribute is used to force capture instead of selecting from the library. See the spec and Correct Syntax for HTML Media Capture
– Octavian Naicu
Nov 9 '16 at 15:56
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ADT requires 'org.eclipse.wst.sse.core 0.0.0' but it could not be found
...the Eclipse components for the SDK. I was able to get DDMS to install when selecting it by itself.
29 Answers
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How to update a menu item shown in the ActionBar?
... set a condition in oncreateOptionMenu().
For example:
Boolean mISQuizItemSelected = false;
/**
* Called to inflate the action bar menus
*
* @param menu
* the menu
*
* @return true, if successful
*/
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu ite...
Is there a performance difference between CTE , Sub-Query, Temporary Table or Table Variable?
...ur question. If you click on the link you will see the reasons those users selected.
– Aaron Bertrand
Jun 23 '12 at 17:13
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Filter by property
...ral models, and this routine should work for all models. And it does:
def selectByProperties(modelType, specify):
clause = "SELECT * from %s" % modelType._meta.db_table
if len(specify) > 0:
clause += " WHERE "
for field, eqvalue in specify.items():
clause += ...
When and why are database joins expensive?
...s back to mitigating the size of the working set. Joins involving properly selected keys with correctly set up indexes are cheap, not expensive, because they allow significant pruning of the result before the rows are materialised.
Materialising the result involves bulk disk reads which are the mo...