I want to search data based on month and year. Then, it will count the same id for Book_id.
I have problems to count the Book_id for monthly. This query will count for entire records including monthly, which is not the result I want.
$res2 = mysql_query( "SELECT DISTINCT Date_borrow, Book_name as nmBook, Book_id as b_id, count(Book_name) AS count
FROM transaksi
GROUP BY nmBook
HAVING count > 1
ORDER BY COUNT DESC ");
$rowss = mysql_fetch_array($res2);
Thanks for your help.
I am taking a shot at it not knowing you complete data model
SELECT DISTINCT Date_borrow, Book_name as nmBook, Book_id as b_id,
count(Book_name) AS count
FROM transaksi
GROUP BY nmBook
HAVING count > 1
ORDER BY COUNT DESC
Should be:
SELECT Date_borrow, Book_name as nmBook, Book_id as b_id,
count(Book_name) AS counter
FROM transaksi
GROUP BY Book_name,Date_borrow,book_id
HAVING count(Book_name) > 1
ORDER BY `counter` DESC;
DISTINCT and GROUP BY are mutually exclusive: Once you use GROUP BY, apply either a function on all the fields or add the fields in the GROUP BY.
HAVING COUNT(Book_name): COUNT needs a parameter, so book_name in this case since that is the same as in your SELECT statement.
Use of just created alias in ORDER BY: Test that. Could be that you need to use COUNT(book_name) there too.
Use of reserved word "COUNT" as alias: Avoid the use of any terms sounding like functions or code in table names, column names, function names etc. Invent your own naming standard which avoids this use of (possibly) reserved key words.
Related
I found the following mysqli query on the internet. It displays top 3 sold cars
//create conection with mysql database.
$conn = mysqli_connect("localhost","root","","cars");
//query
$select = "SELECT ord.*, sum(amount) as amt from orders as ord GROUP BY id_car order by amt desc limit 0,3";
$data = mysqli_query($conn,$select);
This query works fine but I would like if anyone can explain me this first section of the query: SELECT ord.*,
It seems like "ord" refers to orders but is it the same as saying: SELECT * FROM orders??
See table in the screenshot image
orders table
In the query there is orders as ord this gives the orders table an 'alias' of the orders table, so ord.* means orders.*
It is a bit redundant in this query to be honest, mainly used if there are multiople tables in a query :)
For this query you can simply do:
$select = "SELECT *, sum(amount) as amt from orders GROUP BY id_car order by amt desc limit 0,3";
Let's break it down:
a) Select all fields from table named ord which will be defined in c)
SELECT ord.*,
b) Select sum of column amount and name it amt
sum(amount) as amt
c) Use table orders for the query and define an alias name ord for that table, see a)
from orders as ord
It is same as select * from tableName,it will fetch all columns from table.But alias Name is given for the table. Using alias Name is best practices for joining the multiple tables.
since you are using single table you can do this also.
SELECT *, sum(amount) as amt from orders as ord GROUP BY id_car order by amt desc limit 0,3
How can I find the most frequent value in a given column in an SQL table?
For example, for this table it should return two since it is the most frequent value:
one
two
two
three
SELECT
<column_name>,
COUNT(<column_name>) AS `value_occurrence`
FROM
<my_table>
GROUP BY
<column_name>
ORDER BY
`value_occurrence` DESC
LIMIT 1;
Replace <column_name> and <my_table>. Increase 1 if you want to see the N most common values of the column.
Try something like:
SELECT `column`
FROM `your_table`
GROUP BY `column`
ORDER BY COUNT(*) DESC
LIMIT 1;
Let us consider table name as tblperson and column name as city. I want to retrieve the most repeated city from the city column:
select city,count(*) as nor from tblperson
group by city
having count(*) =(select max(nor) from
(select city,count(*) as nor from tblperson group by city) tblperson)
Here nor is an alias name.
Below query seems to work good for me in SQL Server database:
select column, COUNT(column) AS MOST_FREQUENT
from TABLE_NAME
GROUP BY column
ORDER BY COUNT(column) DESC
Result:
column MOST_FREQUENT
item1 highest count
item2 second highest
item3 third higest
..
..
For use with SQL Server.
As there is no limit command support in that.
Yo can use the top 1 command to find the maximum occurring value in the particular column in this case (value)
SELECT top1
`value`,
COUNT(`value`) AS `value_occurrence`
FROM
`my_table`
GROUP BY
`value`
ORDER BY
`value_occurrence` DESC;
Assuming Table is 'SalesLT.Customer' and the Column you are trying to figure out is 'CompanyName' and AggCompanyName is an Alias.
Select CompanyName, Count(CompanyName) as AggCompanyName from SalesLT.Customer
group by CompanyName
Order By Count(CompanyName) Desc;
If you can't use LIMIT or LIMIT is not an option for your query tool. You can use "ROWNUM" instead, but you will need a sub query:
SELECT FIELD_1, ALIAS1
FROM(SELECT FIELD_1, COUNT(FIELD_1) ALIAS1
FROM TABLENAME
GROUP BY FIELD_1
ORDER BY COUNT(FIELD_1) DESC)
WHERE ROWNUM = 1
If you have an ID column and you want to find most repetitive category from another column for each ID then you can use below query,
Table:
Query:
SELECT ID, CATEGORY, COUNT(*) AS FREQ
FROM TABLE
GROUP BY 1,2
QUALIFY ROW_NUMBER() OVER(PARTITION BY ID ORDER BY FREQ DESC) = 1;
Result:
Return all most frequent rows in case of tie
Find the most frequent value in mysql,display all in case of a tie gives two possible approaches:
Scalar subquery:
SELECT
"country",
COUNT(country) AS "cnt"
FROM "Sales"
GROUP BY "country"
HAVING
COUNT("country") = (
SELECT COUNT("country") AS "cnt"
FROM "Sales"
GROUP BY "country"
ORDER BY "cnt" DESC,
LIMIT 1
)
ORDER BY "country" ASC
With the RANK window function, available since MySQL 8+:
SELECT "country", "cnt"
FROM (
SELECT
"country",
COUNT("country") AS "cnt",
RANK() OVER (ORDER BY COUNT(*) DESC) "rnk"
FROM "Sales"
GROUP BY "country"
) AS "sub"
WHERE "rnk" = 1
ORDER BY "country" ASC
This method might save a second recount compared to the first one.
RANK works by ranking all rows, such that if two rows are at the top, both get rank 1. So it basically directly solves this type of use case.
RANK is also available on SQLite and PostgreSQL, I think it might be SQL standard, not sure.
In the above queries I also sorted by country to have more deterministic results.
Tested on SQLite 3.34.0, PostgreSQL 14.3, GitHub upstream.
Most frequent for each GROUP BY group
MySQL: MySQL SELECT most frequent by group
PostgreSQL:
Get most common value for each value of another column in SQL
https://dba.stackexchange.com/questions/193307/find-most-frequent-values-for-a-given-column
SQLite: SQL query for finding the most frequent value of a grouped by value
SELECT TOP 20 WITH TIES COUNT(Counted_Column) AS Count, OtherColumn1,
OtherColumn2, OtherColumn3, OtherColumn4
FROM Table_or_View_Name
WHERE
(Date_Column >= '01/01/2023') AND
(Date_Column <= '03/01/2023') AND
(Counted_Column = 'Desired_Text')
GROUP BY OtherColumn1, OtherColumn2, OtherColumn3, OtherColumn4
ORDER BY COUNT(Counted_Column) DESC
20 can be changed to any desired number
WITH TIES allows all ties in the count to be displayed
Date range used if date/time column exists and can be modified to search a date range as desired
Counted_Column 'Desired_Text' can be modified to only count certain entries in that column
Works in INSQL for my instance
One way I like to use is:
select *<given_column>*,COUNT(*<given_column>*)as VAR1 from Table_Name
group by *<given_column>*
order by VAR1 desc
limit 1
Look at my code, I want the select statement order by the count percentage after I fetch the data from this select statement, obviously, it's not logical. What can I do? Help, appreciate.
<?php
//myslq connection code, remove it because it's not relate to this question
$stm =$db->prepare("SELECT id ,term_count, COUNT(user_id) as count FROM sign WHERE term IN (:term_0,:term_1) GROUP BY user_id ORDER by count DESC");
//trying replace order by count with $combine_count, but it's wrong
$term_0="$term[0]";
$term_1="$term[1]";
$stm->bindParam(":term_0", $term_0);
$stm->bindParam(":term_1", $term_1);
stm->execute();
$rows = $stm->fetchALL(PDO::FETCH_ASSOC);
foreach ($rows as rows) {
$count=$rows['count'];
$term_count_number=$rows['term_count'];
$count_percentage=round(($count/$count_user_diff)*100);
$count_key_match=round(($count/$term_count_number)*100);
$combine_count=round(($count_percentage+$count_key_match)/2);
//issue is here, I want the select statement order by $combine_count
}
?>
SELECT id ,term_count, COUNT(user_id) as `count`
FROM sign
WHERE term IN (:term_0,:term_1)
GROUP BY user_id
ORDER by `count` DESC");
Since "count" is a function, it would be better to put backtics around the non-function "counts", as done above.
GROUP BY should list the field not aggregated. Otherwise, it does not know which id and term_count to fetch. So, depending on what you are looking for,
Either do
SELECT user_id, COUNT(*) as `count` -- I changed this line
FROM sign
WHERE term IN (:term_0,:term_1)
GROUP BY user_id
ORDER by `count` DESC");
or do
SELECT id ,term_count, COUNT(*) as `count`
FROM sign
WHERE term IN (:term_0,:term_1)
GROUP BY id ,term_count -- I changed this line
ORDER by `count` DESC");
SQL Syntax Logic
SELECT column1, count(column1) AS amount
FROM table_name
GROUP BY column1
ORDER BY amount DESC
LIMIT 12
This is basic but I can't figure it out. I have two tables (SeriesTable and OtherTable). SeriesTable has all the information for a given series including its id (column named "seriesid"). And OtherTable has a column called "seriescolumn" which also has the ids of a given series.
I need to make a query that counts every entry in OtherTable's "seriescolumn" that matches the seriesid column in SeriesTable. So for example, if the seriesid in SeriesTable is 5, I need to count how many entries in OtherTable have the value of 5 in the seriescolumn.
Below is my current code that simply grabs the info from the first table, but I have no idea how to correctly count the matching entries from OtherTable.
<?
$rs= mysql_query("SELECT seriesid FROM SeriesTable ORDER BY seriesid DESC");
while ($row= mysql_fetch_array($rs)) { ?>
content
<? } ?>
Sounds like you are going to need a join and group by statement.
SELECT s.seriesid, Count(*) As NumberOfSeries
FROM SeriesTable s Join
OtherTable o On s.seriesid = o.seriescolumn
Group By s.seriesid
ORDER BY seriesid DESC
This should return each seriesid and a count of how many times it was repeated.
Probably the easiest way to do this is in one big SQL query, using the count statement.
You can use a GROUP BY clause to group the result by the seriesid as you want, giving something along the lines of:
SELECT seriesid, COUNT(*) FROM SeriesTable, OtherTable
WHERE seriescolumn=seriesid GROUP BY seriesid
SELECT seriesid, COUNT(seriescolumn)
FROM SeriesTable, OtherTable
WHERE OtherTable.seriescolumn = SeriesTable.seriesid
GROUP BY seriesid;
I need to order my query by date first...
So I used this:
SELECT * FROM `mfw_navnode` order by `id` DESC
I wanted to order my results from last to first.
Then what I am trying to do
is to add a query over it, which would group my results by node_name..
The result should be..all the top nodes grouped by "category/node name type", while the first node that I see is was ordered the highest for its category in the first query..
I thought to do something like this:
SELECT * FROM(
SELECT * FROM `mfw_navnode` order by `id` DESC) AS DD
WHERE (node_name='Eby' OR node_name='Laa' OR node_name='MIF' OR node_name='Amaur' OR node_name='Asn' )
GROUP BY DD.node_name
I get no result..or any response from phpmyadmin when I input that result..
Where do I get wrong?
Note , I dont want to group my results and then order them..
I want them to be ordered, and then grouped. After being grouped..I want the result of each group to have the highest value ..from the other rows in the group
It is not sufficient to perform the ordering first, as even then MySQL makes no guarantee over which record it will select for each group. From the manual:
The server is free to choose any value from each group, so unless they are the same, the values chosen are indeterminate.
You must instead identify the records of interest with a subquery, then join the result with your table again in order to obtain the related values:
SELECT *
FROM mfw_navnode NATURAL JOIN (
SELECT node_name, MAX(id) AS id FROM mfw_navnode GROUP BY node_name
) AS DD
WHERE node_name IN ('Eby', 'Laa', 'MIF', 'Amaur', 'Asn')
Ordered by ID and group by node_name
SELECT * FROM `mfw_navnode`
WHERE (node_name='Eby' OR node_name='Laa' OR node_name='MIF' OR node_name='Amaur' OR node_name='Asn' )
GROUP BY DD.node_name
ORDER BY `id` DESC
Grouping is used commonly when You are using some aggregate function (sum, max, min, count, etc). If You don't use such function in Your query then why do You want to group the results?
Anyway, this should do the trick:
SELECT *
FROM mfw_navnode
WHERE id IN (SELECT id
FROM mfw_navnode
WHERE node_name IN ('Eby', 'Laa', 'MIF', 'Amaur', 'Asn')
GROUP BY node_name)
ORDER BY id
The following SQL may yield you the required output:
SELECT node_name, MAX(id)
FROM mfw_navnode
GROUP BY node_name
ORDER BY node_name
I see two problems with your SQL.
1) placing the order by in the inline select does nothing (and is probably causing an error)
2) you are grouping on node_name but you are not aggregating anything
SELECT COUNT(id) as row_count, node_name FROM( SELECT * FROM mfw_navnode ) AS DD
WHERE (node_name='Eby' OR node_name='Laa' OR node_name='MIF' OR node_name='Amaur' OR node_name='Asn' )
GROUP BY DD.node_name
order by node_name desc
further I am not sure why you need the inline select as the where could simply be on the original select ( perhaps you have something more complex going on that you didn't show )
SELECT COUNT(id) as row_count, node_name
from mfw_navnode
WHERE node_name='Eby' OR node_name='Laa' OR node_name='MIF' OR node_name='Amaur' OR node_name='Asn'
GROUP BY node_name
order by node_name desc