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Why shouldn't I use mysql_* functions in PHP?
... 5.5 and above)
$link = mysql_connect('localhost', 'user', 'pass');
mysql_select_db('testdb', $link);
mysql_set_charset('UTF-8', $link);
With PDO: All you need to do is create a new PDO object. The constructor accepts parameters for specifying the database source PDO's constructor mostly takes fo...
How to select a CRAN mirror in R
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Repository selection screen cannot be shown on your system (OS X), since OS X no longer includes X11. R tries to show you the prompt through X11. Install X11 from http://xquartz.macosforge.org/landing/. Then run the install command. The...
SQL SELECT speed int vs varchar
...k: A=261MB B=292MB C=322MB
Non-indexed by id: select count(*), select by id: 450ms same on all tables
Insert* one row per TX: B=9ms/record C=9ms/record
Bulk insert* in single TX: B=140usec/record C=180usec/record
Indexed by id, select by id: B=about 2...
Pass Array Parameter in SqlCommand
...AddWithValue(parameters[i], items[i]);
}
cmd.CommandText = string.Format("SELECT * from TableA WHERE Age IN ({0})", string.Join(", ", parameters));
cmd.Connection = new SqlConnection(connStr);
UPDATE: Here is an extended and reusable solution that uses Adam's answer along with his suggested edit....
Write a number with two decimal places SQL server
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try this
SELECT CONVERT(DECIMAL(10,2),YOURCOLUMN)
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Difference between Select and ConvertAll in C#
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Select is a LINQ extension method and works on all IEnumerable<T> objects whereas ConvertAll is implemented only by List<T>. The ConvertAll method exists since .NET 2.0 whereas LINQ was introduced with 3.5.
You s...
How to find all the tables in MySQL with specific column names in them?
... all tables with columns columnA or ColumnB in the database YourDatabase:
SELECT DISTINCT TABLE_NAME
FROM INFORMATION_SCHEMA.COLUMNS
WHERE COLUMN_NAME IN ('columnA','ColumnB')
AND TABLE_SCHEMA='YourDatabase';
...
Transferring an app to another Firebase account
...another account. All you have to do is:
Go to your Firebase console, and select the project you want to shift.
Select the cog icon besides the project name on top right.
Select Permissions from the flyout.
Select Advanced permission settings hyperlink.
You've reached the IAM & Admin page of Fi...
How can I remove duplicate rows?
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Assuming no nulls, you GROUP BY the unique columns, and SELECT the MIN (or MAX) RowId as the row to keep. Then, just delete everything that didn't have a row id:
DELETE FROM MyTable
LEFT OUTER JOIN (
SELECT MIN(RowId) as RowId, Col1, Col2, Col3
FROM MyTable
GROUP BY Co...
Importing a Maven project into Eclipse from Git
...t. M2Eclipse will help you along by prompting you on the Import menu.
Select the "Import..." context menu from the Package Explorer view
Select "Check out Maven projects from SCM" option under the Maven category
On the window that is presented choose the link "Find more SCM connectors in the m2...