You can use the sp_who stored procedure. Provides information about current users, sessions, and processes in an instance of the Microsoft SQL Server Database Engine. The information can be filtered to return only those processes that are not idle, that belong to a specific user, or that belong to a specific session.
Here’s a list of differences. I’ve highlighted Oracle-specific features, and hopefully the community can add in other vendors’ specific difference also. Differences that are common to most vendors can go directly below the headings, with differences highlighted below. General Overview If you want to quickly delete all of the rows from a table, and you’re … Read more
float Or if you want to go old-school: real You can also use float(53), but it means the same thing as float. (“real” is equivalent to float(24), not float/float(53).) The decimal(x,y) SQL Server type is for when you want exact decimal numbers rather than floating point (which can be approximations). This is in contrast to … Read more
This basically is a pivot table. A nice tutorial on how to achieve this can be found here: http://www.artfulsoftware.com/infotree/qrytip.php?id=78 I advise reading this post and adapt this solution to your needs. Update After the link above is currently not available any longer I feel obliged to provide some additional information for all of you searching … Read more
Same question was asked on MSDN Forums: Varchar(max) vs Varchar(255) From the original post (much more information there): When you store data to a VARCHAR(N) column, the values are physically stored in the same way. But when you store it to a VARCHAR(MAX) column, behind the screen the data is handled as a TEXT value. … Read more
There’s several different ways of doing this, with varying efficiency, depending on how good your query optimiser is, and the relative size of your two tables: This is the shortest statement, and may be quickest if your phone book is very short: SELECT * FROM Call WHERE phone_number NOT IN (SELECT phone_number FROM Phone_book) alternatively … Read more
From the fine manual: ALTER TABLE mytable ALTER COLUMN mycolumn DROP NOT NULL; There’s no need to specify the type when you’re just changing the nullability.
For latitudes use: Decimal(8,6), and longitudes use: Decimal(9,6) If you’re not used to precision and scale parameters, here’s a format string visual: Latitude and Longitude ##.###### and ###.###### To 6 decimal places should get you to around ~10cm of accuracy on a coordinate.
How about this UPDATE table SET columnB = columnA; This will update every row.
Quite simple actually: SELECT * FROM `table` WHERE `column` LIKE ‘%{$needle}%’ The % is a wildcard for any characters set (none, one or many). Do note that this can get slow on very large datasets so if your database grows you’ll need to use fulltext indices.