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What is cardinality in MySQL?
...ow cardinality column with only 2 possible values as the index will not be selective enough to be used.
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“Remote System Explorer Operation” causing freeze for couple of seconds
...
Here are the steps:
Click on the Windows > Preferences menu
Select General > Workspace > Build in the tree
Uncheck Use default build order
Select RemoteSystemsTempFiles
Click Remove Project
Click Apply and Close
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SQLAlchemy ORDER BY DESCENDING?
...
from sqlalchemy import desc
someselect.order_by(desc(table1.mycol))
Usage from @jpmc26
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Using psql how do I list extensions installed in a database?
...org/docs/current/static/app-psql.html
Doing it in plain SQL it would be a select on pg_extension:
SELECT *
FROM pg_extension
http://www.postgresql.org/docs/current/static/catalog-pg-extension.html
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Entity Framework with NOLOCK
...SMS, open a query (#1) and run: CREATE TABLE ##Test(Col1 INT); BEGIN TRAN; SELECT * FROM ##Test WITH (TABLOCK, XLOCK);. Open another query (#2) and run: SELECT * FROM ##Test;. The SELECT won't return as it is being blocked by the still open transaction in tab #1 that is using an exclusive lock. Canc...
java.lang.ClassNotFoundException: Didn't find class on path: dexpathlist
...d a similar problem, here's my solution:
Right click on your project and select Properties.
Select Java Build Path from the menu on the left.
Select the Order and Export tab.
From the list make sure the libraries or external jars you added to your project are checked.
Finally, clean your project &...
How to get all groups that a user is a member of?
...alGroupMembership will do this.
Get-ADPrincipalGroupMembership username | select name
name
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Domain Users
Domain Computers
Workstation Admins
Company Users
Company Developers
AutomatedProcessingTeam
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Where are my postgres *.conf files?
...alives_idle = 0 # TCP_KEEPIDLE, in seconds;
# 0 selects the system default
#tcp_keepalives_interval = 0 # TCP_KEEPINTVL, in seconds;
# 0 selects the system default
#tcp_keepalives_count = 0 # TCP_KEEPCNT;
# 0 selects the...
Postgresql query between date ranges
... things become simpler if you use >= start AND < end.
For example:
SELECT
user_id
FROM
user_logs
WHERE
login_date >= '2014-02-01'
AND login_date < '2014-03-01'
In this case you still need to calculate the start date of the month you need, but that should be straight forw...
Making a UITableView scroll when text field is selected
... defaultCenter] addObserver:self
selector:@selector(keyboardWillShow:)
name:UIKeyboardWillShowNotification
object:nil];
// Register notification when the keyboard will b...