i have 2 tables:
1st table is called maxlift with 1 column called, exercise
2nd table is called workout with 5 columns called, exercise, sets, reps, weight, date
i want display the highest weight for each exercise where exercise in both tables is the same.
i am using:
`SELECT *
FROM workout, maxlift
WHERE workout.exercise = maxlift.exercise
GROUP BY maxlift.exercise
ORDER BY workout.weight desc`
the problem i have is the weight displayed is not the highest weight from table workout.
thanks for any help.
You can use the aggregate function max() for this.
SELECT workout.exercise, max(weight) as weight
FROM workout, maxlift
WHERE workout.exercise=maxlift.exercise
GROUP BY workout.exercise;
Now, you basically group by exercise and find the maximum weight for each such group using the max() function. You can alias your selected column using column_name as alias.
`SELECT *
FROM workout, maxlift
WHERE workout.exercise = maxlift.exercise
ORDER BY workout.weight desc`
use this by removing group by and let me know about it
Related
I'm trying to change two SQL queries I have right now so that in addition to giving me a result from a table, it only gives me that result based on the newest say 150 entries within the table.
My two queries at the moment are:
SELECT COUNT(*)
FROM `stock`.`replacements.archive`
WHERE `ciref` = '$cihistory'
and
SELECT `req_model`, COUNT(`req_model`) AS `value_occurrence`
FROM `stock`.`replacements.archive`
GROUP BY `req_model`
ORDER BY `value_occurrence` DESC LIMIT 5
Is there a way for me to achieve this?
The id field in the table is used as normal so guessing would use this but im not sure how to achieve it
The aim here is to only do the counting of the variable based on the latest 150 entries in the table, i dont want to count everything in the table.
Anyone has any ideas it would be much appreciated!
Thanks
assuming you have an autoincremnt id the you could select the newest 150 entry as
SELECT *
FROM `stock`.`replacements.archive`
ORDER BY id limit 150
and then perform the query on this subquery as
SELECT `req_model`, COUNT(`req_model`) AS `value_occurrence`
FROM (
SELECT *
FROM `stock`.`replacements.archive`
ORDER BY id DESC limit 150
) t
GROUP BY `req_model`
ORDER BY `value_occurrence`
Maybe a stupid question, but I can't find anything on it. I know you can do counts and some basic math with queries.
Is there a way to make the database count and return results with the highest or lowest number of occurrences?
Lets say you had all the pages of a library in a database and you wanted to know the top 5 characters used or maybe the least used.
I guess the easiest example would be the lottery. Lets say you had a table of past lottery results. Lets say you wanted to return a list of the top 10 most drawn numbers. Lets say the numbers can range from 1 to 100.
It wouldn't be very efficient to run the following query 100 different times and then run some php to sort the data.
SELECT COUNT(*) FROM mytable WHERE ball=1
Surely there must be a way to return a count of the most duplicated data.
Perhaps I am over thinking this. Anyway, thanks for any help in the matter.
That's called grouping, the group by clause will let you do that, make sure you don't just pull out the count but also the thing you're counting, in this case ball.
Get the lowest number occurrences:
SELECT ball, COUNT(*) FROM mytable GROUP BY ball ORDER BY ball ASC limit 1;
Get the highest number occurrences:
SELECT ball, COUNT(*) FROM mytable GROUP BY ball ORDER BY ball DESC limit 1;
If you want them all in one result you can use a union/union all:
(SELECT ball, COUNT(*) FROM mytable GROUP BY ball ORDER BY ball ASC limit 1)
UNION ALL
(SELECT ball, COUNT(*) FROM mytable GROUP BY ball ORDER BY ball DESC limit 1);
you can simply use
SELECT column, COUNT(*)
FROM mytable
GROUP BY column_name
this will count all of the existing entries for the specific column_name
you should use column before COUNT(*) so you know what has that many values.
i hope this helps!
I need to create a autocomplete search with ajax. The suggestions should only contain the 10 most entered results. The search query has to check multiple columns if the value is like my variable.
But my problem is to create the query and the php logic for that.
Is there any plugin or something simular for that?
How can I select a column if the value in it is like my variable?
I need to create a count query, which counts (in all columns) "how often is here the full word (splitted by spaces)" <- which is like the found one (to get the relevance)
At the end I need to sort the found entries by their relevance to provide the 10 most relevant entries.
(The real query checks for more columns than just 2, but for dummy reasons are 2 okay)
The query which selects the rows where the value is like...
select * from
(
(select department from entries where department like '%myVariable%')
OR
(select grade from entries where grade like '%myVariable%')
)
I think you know what I mean. Does anyone have any hints, suggestions, examples or useful links for me?
Thanks in advance!
Best regards,
FriaN
Why not use union all here?
select department from entries where department like '%myVariable%'
union all
select grade from entries where grade like '%myVariable%'
Then this should order the results for you:
select department, count(*) cnt from (
select department from entries where department like '%myVariable%'
union all
select grade from entries where grade like '%myVariable%')a
group by department
order by count(*) desc
I'm working on php small project, here I need first 5 records from beginning of records and last record 1 from end of the table's record. I don't know how to write a single mysqli query.
Any help will be appreciated. Thanks in advance.
SQL tables represent unordered sets. So, there is no such thing as the first five rows or last row -- unless a column explicitly defines the ordering.
Often, a table has some sort of auto-incremented id column, which can be used for this purpose. If so, you can do:
(select t.*
from t
order by id asc
limit 5
) union all
(select t.*
from t
order by id desc
limit 1
);
Notes:
Sometimes, an insert date/time column is the appropriate column to use.
You want to use union all rather than union -- unless you want to incur the overhead of removing duplicate values.
For this formulation, if there are fewer than 6 rows, then you will get a duplicate.
The UNION operator allows this, carefully toying with the ORDER BY and LIMIT clauses :
(SELECT * FROM table ORDER BY field ASC LIMIT 5)
UNION
(SELECT * FROM table ORDER BY field DESC LIMIT 1)
I want order a selection of items by the rating. There are 2 fields: rateup and ratedown. I use these fields to calculate a number and order the selection on that number. Can that be done in mysql? I have a querylike this, but this doesn't work:
SELECT * FROM table ORDER BY (((9/rateup+ratedown)*rateup)+1) DESC
How can I make this work or is this impossible?
Select *, (((9/rateup+ratedown)*rateup)+1) As Ord from Table WHERE published = 1 Order By Ord Desc
added Where Clause as requested.