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When should I use a composite index?
..._C )
will benefit a query that uses those fields for joining, filtering, and sometimes selecting. It will also benefit queries that use left-most subsets of columns in that composite. So the above index will also satisfy queries that need
index( column_A, column_B, column_C )
index( column_A, col...
Get current AUTO_INCREMENT value for any table
...EMENT`
FROM INFORMATION_SCHEMA.TABLES
WHERE TABLE_SCHEMA = 'DatabaseName'
AND TABLE_NAME = 'TableName';
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Bold words in a string of strings.xml in Android
...have a long text in one of the strings at strings.xml. I want to make bold and change the color of some words in that text.
...
SQL Server add auto increment primary key to existing table
...lues when you do this:
ALTER TABLE dbo.YourTable
ADD ID INT IDENTITY
and then you can make it the primary key:
ALTER TABLE dbo.YourTable
ADD CONSTRAINT PK_YourTable
PRIMARY KEY(ID)
or if you prefer to do all in one step:
ALTER TABLE dbo.YourTable
ADD ID INT IDENTITY
CONSTRA...
Cannot truncate table because it is being referenced by a FOREIGN KEY constraint?
...
After deleting large data, user have to shrink the tables and log files also to reclaim the disk space.
– Muhammad Yousaf Sulahria
Oct 22 '16 at 16:15
...
Defining a percentage width for a LinearLayout? [duplicate]
...0%) for a LinearLayout that contains some buttons, so that I can center it and so that the child buttons can fill_parent. Here's a picture showing what I mean:
...
sqlalchemy flush() and get inserted id?
...re populated immediately within the flush() process as they are generated, and no call to commit() should be required. So the answer here lies in one or more of the following:
The details of your mapping
If there are any odd quirks of the backend in use (such as, SQLite doesn't generate integer v...
Remove duplicates in the list using linq
... , What will be the change in code if i have a List<my_Custom_Class> and List<string>. My custom class has various items in which one is DCN number and list<string> has only DCN number. So I need to check the List<Custom_Class> contains any dcn from List<string>. For ex...
How to change ProgressBar's progress indicator color in Android
.... This is from the layout that has the progress bar:
<ProgressBar
android:id="@+id/ProgressBar"
style="?android:attr/progressBarStyleHorizontal"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:indeterminate="false"
android:maxHeight="10dip...
SQL JOIN - WHERE clause vs. ON clause
... JOIN OrderLines ON OrderLines.OrderID=Orders.ID
WHERE Orders.ID = 12345
and
SELECT *
FROM Orders
LEFT JOIN OrderLines ON OrderLines.OrderID=Orders.ID
AND Orders.ID = 12345
The first will return an order and its lines, if any, for order number 12345. The second will return all orders, but...