A long time XP user, I was very nervous about getting a new system with windows 7. Would anything work? Would it be slower? All kinds of things ran through my head. I read all the reviews and for the most part, it seemed like a sucessful release, but then?……..
|
||||||
|
Have you ever had a situation where you needed to select rows from a table for a specific month? This example demonstrates how to retrieve all of the records belonging to the previous month by setting the first and last days in the WHERE clause of a SELECT statement. But with some tweaking, you can make this query retrieve data from any month you wish. Continue reading → Getting records based on the first and last days of a month This is the last post about HADR, I think I covered most of the basics of HADR finishing off with how it switches primary and standby. What I have gone over is the basics of HADR. There are many other topics within HADR. One important thing to remember is to NEVER do unlogged operations (careful with the load command). Not only will it ‘break’ HADR standby, but it will not tell you — you’ll not find out until you switch over to the standby to find it unusable. I believe that in version 9.7, we are being allowed access to the standby. This will allow you to validate the usability of the standby as well as other things like reporting. Okay, so here we go …. setting up an hadr environment…. HADR in it’s lowest form is very straight forward to set up. Here are the steps to start HADR HADR is a very easy and effective way to maintain a DR and/or standby for any given database. You can implement it very quickly and simply and it works well. In essence it is basically log shipping, but done in real time and elegantly. It is not replication, so the standby database is not really accessible when in stand by mode. As well, since it is basically log shipping, any operation that is not logged will not make it to the standby database. Load operations can be a problem as are things like tables with ‘not logged initially’. You will have to review your own situations as they arise. Excel is a wonderful tool that can be used to write sql using substitution from cells to cusomize and update or insert. One problem has always been dates… they never come out right To find text in a directory of files, use the following Windows command (it’s faster than Windows Search):
Hi folks, Have you ever had a requirement to number the results of a sql query? There are some occassions wheer you want to identify the nth record of a result and it can sometimes be a tricky thing to do. One of the reasons you might want to number the results is to create a mechanizm to produce pageable results. For example, if you had an application that wants to have ‘pages’ where page one has the first 30 rows returned and page two has the second 30 rows and so on….. it could become onerous to have the application do all of this work. It might be easier for the sql to just return the rows (or pages) you want as indicated by the app. To do this you need to know what rows qualify and to do that you need to number them…. Here is the trick….. Continue reading → How to number your sql results Some time ago, we upgraded our DB2 from version 7 to 8.2. One of the first things we noticed was that connection times from our client were very long - in the area of about 15 to 20 seconds just to connect to an active database. Continue reading → Slow DB2 connect problem from client |
||||||
|
Copyright © 2010 DBMSguy.com - All Rights Reserved |
||||||