i've create a database to store statistics from a website such as traffic. i'm trying to query the database for the number of unique ip addresses that have been captured over the last 30 days;
SELECT COUNT(*) totalA FROM statistics GROUP by ipAddress
AND DATE_SUB(CURDATE( ) ,INTERVAL 30 DAY) LIMIT 0, 30
however the query just return the number of data entry in the table. i've used the same query minus the date filter and gotten the correct result so it's just the date filtering thats messed up
any help would be appreciated thanks
It's because you're GROUP BY on the ipAddress AND DATE_SUB(CURDATE( ), INTERVAL 30 DAY) and this expression yields the logical AND between two fields, which has only 2 possible values. Still, you don't care bout the distinction and request just count(*).
What you probably want is:
SELECT ipAddress, DATE_SUB(CURDATE( ), INTERVAL 30 DAY), COUNT(*) AS totalA
FROM statistics
GROUP by ipAddress, DATE_SUB(CURDATE( ), INTERVAL 30 DAY)
LIMIT 0, 30
I think this is what you are looking for. Basically I just put your date code in a WHERE clause and compared it to the date column in your table. Obviously you will need to change the "entryDate" to whatever the name of your date column is.
SELECT COUNT(*) AS totalA
FROM statistics
WHERE entryDate >= DATE(CURDATE()-INTERVAL 30 DAY)
GROUP BY ipAdress
Related
Users can sign up for a premium listing for a specified number of days, e.g. 30 days.
tblPremiumListings
user_id days created_date
---------------------------------
1 30 2013-05-21
2 60 2013-06-21
3 120 2012-06-21
How would I select records where there are still days remaining on a premium listing.
SELECT *
FROM tblPremiumListings
WHERE created_date + INTERVAL `days` DAY >= CURDATE()
It's easiest to read with INTERVAL
select *
from tblPremiumListings
where created_date + interval days day >= now();
But I would also change the table to instead of created_date and days instead store end_date. That way the query is
select *
from tblPremiumListings
where end_date >= now();
The benefit of doing like this is that you can put an index on end_date and quickly find all ended premium listings, with your original table you'll always have to do a full table scan to find the records with expired listing.
SELECT * FROM
tblPremiumListings
WHERE (DATEDIFF(NOW(), created_date) - days) <= 0
See if it solves your problem
One way to get the result:
SELECT t.user_id
, t.days
, t.created_date
FROM tblPremiumListings t
WHERE t.created_date + INTERVAL t.days DAY > DATE(NOW())
You may want a >= comparison operator (instead of >) depending on how you define days remaining.
NOTE: the access plan for this query will be full scan of all rows, since MySQL won't be able to do a range scan on an index. For large sets, having a column that can be indexed to satisfy the query may improve performance, e.g.
WHERE t.expire_date > DATE(NOW())
Try this one...
SELECT * FROM
tblPremiumListings
WHERE DATE_ADD(created_date, days)>DATE(NOW())
I have a number of posts saved into a InnoDB table on MySQL. The table has the columns "id", "date", "user", "content". I wanted to make some statistic graphs, so I ended up using the following query to get the amount of posts per hour of yesterday:
SELECT HOUR(FROM_UNIXTIME(`date`)) AS `hour`, COUNT(date) from fb_posts
WHERE DATE(FROM_UNIXTIME(`date`)) = CURDATE() - INTERVAL 1 DAY GROUP BY hour
This outputs the following data:
I can edit this query to get any day I want. But what I want now is the AVERAGE of each hour of every day, so that if on Day 1 at 00 hours I have 20 posts and on Day 2 at 00 hours I have 40, I want the output to be "30". I'd like to be able to pick date periods as well if it's possible.
Thanks in advance!
You can use a sub-query to group the data by day/hour, then take the average by hour across the sub-query.
Here's an example to give you the average count by hour for the past 7 days:
select the_hour,avg(the_count)
from
(
select date(from_unixtime(`date`)) as the_day,
hour(from_unixtime(`date`)) as the_hour,
count(*) as the_count
from fb_posts
where `date` >= unix_timestamp(current_date() - interval 7 day)
and created_on < unix_timestamp(current_date())
group by the_day,the_hour
) s
group by the_hour
Aggregate the information by date and hour, and then take the average by hour:
select hour, avg(numposts)
from (SELECT date(`date`) as day, HOUR(FROM_UNIXTIME(`date`)) AS `hour`,
count(*) as numposts
from fb_posts
WHERE DATE(FROM_UNIXTIME(`date`)) between <date1> and <date2>
GROUP BY date(`date`), hour
) d
group by hour
order by 1
By the way, I prefer including the explicit order by, since most databases do not order the results of a group by. Mysql happens to be one database that does.
SELECT
HOUR(FROM_UNIXTIME(`date`)) AS `hour`
, COUNT(`id`) \ COUNT(DISTINCT TO_DAYS(`date`)) AS avgHourlyPostCount
FROM fb_posts
WHERE `date` > '2012-01-01' -- your optional date criteria
GROUP BY hour
This gives you a count of all the posts, divided by the number of days, by hour.
I have a CHANGES table with fields VALUE(integer) and CREATED_AT(timestamp). I want to know the total of the VALUE column grouped by each of the past 30 days (without making 30 queries).
So if yesterday there were records created with VALUEs of 10, -7, and 12; I would want a record returned with CREATED_AT = yesterday and TOTAL = 15.
Any help?
SELECT date(created_at) as CREATED_AT, sum(value) as TOTAL
FROM changes
WHERE created_at >= curdate() - interval 30 day
GROUP BY date(created_at);
Well, it slightly depends on what kind the timestamp is formatted in (SQL/ Unix/ etc). But this type of query might help you along:
SELECT
DATE_FORMAT(CREATED_AT, '%Y-%m-%d') ym,
COUNT(VALUE)
FROM foo
GROUP BY ym
Suppose you have a table of the form:
create table user_activity (
user_id int not null,
activity_date timestamp not null,
...);
It's easy enough to select the number of unique user_id's in the past 30 days.
select count(distinct user_id) from user_activity where activity_date > now() - interval 30 day;
But how can you select the number of unique user_ids in the prior 30 days for each of the past 30 days? E.g. uniques for 0-30 days ago, 1-31 days ago, 2-32 days ago and so on to 30-60 days ago.
The database engine is mysql if it matters
You could try using a sub query:
SELECT DISTINCT `activity_date` as `day`, (
SELECT count(DISTINCT `user_id`) FROM `user_activity` WHERE `activity_date` = `day`
) as `num_uniques`
FROM `user_activity`
WHERE `activity_date` > NOW() - INTERVAL 30 day;
This should give you the number of unique users for each day. However, I haven't tested this since I don't have the DB to work with.
I haven't tried this in MySQL, but hopefully the syntax is right. If not, maybe it will point you in the right direction. First, I often employ a Numbers table. It can be a physical table simply made up of numbers or it can be a generated/virtual/temporary table.
SELECT
N.number,
COUNT(DISTINCT UA.user_id)
FROM
Numbers N
INNER JOIN User_Activity UA ON
UA.activity_date > NOW() - INTERVAL 30 + N.number DAY AND
UA.activity_date <= NOW() - INTERVAL N.number DAY
WHERE
N.number BETWEEN 0 AND 30
GROUP BY
N.number
I'm not familiar with the whole INTERVAL syntax, so if I got that wrong, please let me know and I'll try to correct it.
If you get the days number for todays date and mod it by 30 you get the offset of the current day. Then you add that to each number for a date and divide the result by 30, this gives you the group of days. Then group your results by this number. So in code something like this:
select count(distinct user_id), (to_days(activity_date)+(to_days(now()) % 30)) / 30 as period
from user_activity
group by (to_days(activity_date)+(to_days(now()) % 30)) / 30
I will leave calculating the reverse numbering of period up to you (hint: take the period number for the current date as "max" and subtract period above and add 1.)
I always have trouble with complicated SQL queries.
This is what I have
$query = '
SELECT id,
name,
info,
date_time
FROM acms_events
WHERE date_time = DATE_SUB(NOW(), INTERVAL 1 HOUR)
AND active = 1
ORDER BY date_time ASC
LIMIT 6
';
I want to get up to 6 rows that are upcoming within the hour. Is my query wrong? It does not seem to get events that are upcoming within the next hour when I test it.
What is the correct syntax for this?
I'm going to postulate that you're looking at a group of records that contain a range of DATETIME values, so you probably want something more like this:
SELECT id,
name,
info,
date_time
FROM acms_events
WHERE date_time < DATE_ADD(NOW(), INTERVAL 1 HOUR)
AND date_time >= NOW()
AND active = 1
ORDER BY date_time ASC
LIMIT 6
Otherwise, your query is looking for records with a date_time of exactly "now + 1 hour". I'm assuming all your dates aren't specific to that particular second. ;)
To clarify a bit, DATE_ADD() and DATE_SUB() return exact timestamps, so your query above roughly translates to something like SELECT ... WHERE date_time = '2010-04-14 23:10:05' ORDER BY ..., which I don't think is what you want.
WHERE date_time = DATE_SUB(NOW(), INTERVAL 1 HOUR)
means date_time equals exactly now minus one hour, which would result in any record exactly one hour old.
Why not use
WHERE TIMEDIFF(date_time, NOW()) < '01:00:00'
AND date_time > NOW()