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Select n random rows from SQL Server table
I've got a SQL Server table with about 50,000 rows in it. I want to select about 5,000 of those rows at random. I've thought of a complicated way, creating a temp table with a "random number" column, copying my table into that, looping through the temp table and updating each row with RAND() , and ...
How to show SQL queries run in the Rails console?
...ecord::Relation’s to_sql method:
User.where(:id => 3).to_sql
#=> "SELECT \"users\".* FROM \"users\" WHERE \"users\".\"id\" = 3"
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Is there any simple way to find out unused strings in Android project?
...ed Resources....
Click Preview to see what the unused resources are and selectively remove them.
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How to update Identity Column in SQL Server?
...it.
But here are steps to do it, Please take a back-up of table
Step 1- Select design view of the table
Step 2- Turn off the identity column
Now you can use the update query.
Now redo the step 1 and step 2 and Turn on the identity column
Reference
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In C#, why is String a reference type that behaves like a value type?
A String is a reference type even though it has most of the characteristics of a value type such as being immutable and having == overloaded to compare the text rather than making sure they reference the same object.
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List all tables in postgresql information_schema
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You should be able to just run select * from information_schema.tables to get a listing of every table being managed by Postgres for a particular database.
You can also add a where table_schema = 'information_schema' to see just the tables in the informat...
Android selector & text color
...or/button_dark_text.xml
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true"
android:color="#000000" /> <!-- pressed -->
<item android:state_focused="true"
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Postgresql - change the size of a varchar column to lower length
... really large table (almost 30 millions rows).
One of its columns is a varchar(255) and I would like to resize it to a varchar(40) .
Basically, I would like to change my column by running the following command:
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Does a break statement break from a switch/select?
I know that switch / select statements break automatically after every case. I am wondering, in the following code:
6 Ans...
Unable to open project… cannot be opened because the project file cannot be parsed
...here projectname will be the name of your project. Now after right clicked select Show Packages Contents. After that open your projectname.pbxproj file in a text editor. Now search for the line containing <<<<<<< .mine, ======= and >>>>>>> .r. For example in...