Re: Help with a SQL query
От | Mark Nielsen |
---|---|
Тема | Re: Help with a SQL query |
Дата | |
Msg-id | 3C62EB58.7050004@kepnet.net обсуждение исходный текст |
Список | pgsql-sql |
Dan Smith wrote: > Can someone help me figure out a SQL query to do this? > > I have a table with 3 columns: date, count, host. It records the > number of operations per day by a specific host. There are usually 3 > or 4 entries per day per host. I can do max(count)-min(count) to > figure out how many operations per day were completed. What I need is > a query that will output 3 columns: date, host1, host2; the rows will > be the per-day counts. For example: > > Date Host1 Host2 > ---- ----- ----- > Feb-2 25 19 > Feb-3 20 29 > Feb-4 4 18 It is a pretty long sql command, but basically, 1. select a list of unique dates, then select a list of unique hosts, and then select a count for the hits per host per date. I don't think it is easy to list it out the way you want since thereare an unknown number of hosts. I would create an sql query to list it out date host value instead. Then, use your scripting language to organize the data the way you want it. THe problem is you have an unknow number of hosts. I would just use a perl script (or python, php), to select the information, add it up, and the reformat it to print it out in the way you want. I wouldn't bother doing this all in sql. I think some of it has to be done in a programming language. But I am not a total guru, so maybe there is a way. Mark
В списке pgsql-sql по дате отправления: