http://blogs.msdn.com/sqlserverstorageengine/archive/2007/09/30/data-compression-why-do-we-need-it.aspxAs announced in Tech-Ed 2007, data compression is a new and exciting feature targeted to be available in SQL Server 2008. This is a huge topic to be covered in one BLOG post, I have decided to break it into a series of posts, each building on the previousenCommunityServer 2.1 SP1 (Build: 61025.2)http://blogs.msdn.com/sqlserverstorageengine/archive/2007/09/30/data-compression-why-do-we-need-it.aspx#5204321Sun, 30 Sep 2007 03:18:00 GMT91d46819-8472-40ad-a661-2c78acb4018c:5204321Techy News Blog » Data Compression: Why Do we need it?<p>PingBack from <a rel="nofollow" target="_new" href="http://www.artofbam.com/wordpress/?p=3939">http://www.artofbam.com/wordpress/?p=3939</a></p> http://blogs.msdn.com/sqlserverstorageengine/archive/2007/09/30/data-compression-why-do-we-need-it.aspx#5205793Sun, 30 Sep 2007 07:55:17 GMT91d46819-8472-40ad-a661-2c78acb4018c:5205793rdeng<p>very good article, i think it is helpful for me and some others.</p> http://blogs.msdn.com/sqlserverstorageengine/archive/2007/09/30/data-compression-why-do-we-need-it.aspx#5212883Sun, 30 Sep 2007 21:19:38 GMT91d46819-8472-40ad-a661-2c78acb4018c:5212883SQL Server, BI and .NET<p>Dal team dello Storage Engine di SQL Server arrivano alcune notizie interessanti a proposito delle nuove</p> http://blogs.msdn.com/sqlserverstorageengine/archive/2007/09/30/data-compression-why-do-we-need-it.aspx#5216791Mon, 01 Oct 2007 03:16:08 GMT91d46819-8472-40ad-a661-2c78acb4018c:5216791MichaelDotNet<p>I always wondered why previous SQL editions didn't at least include compression for database backup and restore. &nbsp;I always ended up compressing my backups and was surprised at the ratios achieved. &nbsp;One question though, doesn't compressed data actually require /more/ memory since both the compressed data and decompressed data has to be stored at a time? &nbsp;Though I guess selective compression and decompression mitigates some of that to the point where it's beneficial...</p> http://blogs.msdn.com/sqlserverstorageengine/archive/2007/09/30/data-compression-why-do-we-need-it.aspx#5217780Mon, 01 Oct 2007 06:12:34 GMT91d46819-8472-40ad-a661-2c78acb4018c:5217780Sunil Agarwal<p>Yes, backup compression was requested before as well. We finally did it! On your other question, we only store compressed data so only 1 copy. We de-compress at a row level when the row is retrieved. </p> http://blogs.msdn.com/sqlserverstorageengine/archive/2007/09/30/data-compression-why-do-we-need-it.aspx#5225235Mon, 01 Oct 2007 19:48:19 GMT91d46819-8472-40ad-a661-2c78acb4018c:5225235MichaelDotNet<p>Aren't you then having a copy of the row in compressed form and a copy of the row in decompressed form both in memory at the same time? :)</p> <p>Of course that still is a huge memory savings with all the other rows compressed for a single table, and the larger the table the greater the savings, so I get that..</p>http://blogs.msdn.com/sqlserverstorageengine/archive/2007/09/30/data-compression-why-do-we-need-it.aspx#5225536Mon, 01 Oct 2007 20:27:18 GMT91d46819-8472-40ad-a661-2c78acb4018c:5225536Sunil Agarwal<p>Like I was saying, we keep the data compressed. WE de-compress only when the row is needed. So at that time, there are two copies of the row (actually of the requested columns), one that is compressed and other that is not. Note, this is for 'that' row only</p> http://blogs.msdn.com/sqlserverstorageengine/archive/2007/09/30/data-compression-why-do-we-need-it.aspx#5225537Mon, 01 Oct 2007 20:27:22 GMT91d46819-8472-40ad-a661-2c78acb4018c:5225537Sunil Agarwal<p>Like I was saying, we keep the data compressed. WE de-compress only when the row is needed. So at that time, there are two copies of the row (actually of the requested columns), one that is compressed and other that is not. Note, this is for 'that' row only</p>