I have the table:
id | date_submitted
1 | 01/01/2017
1 | 01/02/2017
2 | 01/03/2017
2 | 01/04/2017
I'm looking for the correct SQL to select each row, limited to one row per id that has the latest value in date_submitted.
So the SQL should return for the above table:
id | date_submitted
1 | 01/02/2017
2 | 01/04/2017
The query needs to select everything in the row, too.
Thanks for your help.
You can find max date for each id in subquery and join it with the original table to get all the rows with all the columns (assuming there are more columns apart from id and date_submitted) like this:
select t.*
from your_table t
inner join (
select id, max(date_submitted) date_submitted
from your_table
group by id
) t2 on t.id = t2.id
and t.date_submitted = t2.date_submitted;
Note that this query will return multiple rows for an id in case there are multiple rows with date_submitted equals to max date_submitted for that id. If you really want only one row per id, then the solution will be a bit different.
If you just need id and max date use:
select id, max(date_submitted) date_submitted
from your_table
group by id
I have a mysql table with multiple columns. The primary key of the table is the 'id' column. A row has multiple columns but the most relevant one for this question is 'Date' which is basically a timestamp. What is an efficient way to get the order (rank) of a given row id if I want to order the rows by their timestamp. The most recent timestamp is of rank 1, the second is of rank 2 and so on. I want to return the rank of a given row
Edit: I use ORDER BY to get an ordered set but I want the mysql statement to return the order of the specific item, not an ordered rows. I also don't want to parse the result set since this is very time cosnuming
Edit2: for example assume the following table
id timestamp name
1 Dec 4, 2016 Bob
2 Jan 1, 2015 Eve
3 Feb 6, 2017 Alice
Given an id, I should return the order of the item
id=1, expected output: 2
id=2, expected output: 3 (least recent)
id=3, expected output: 1 (most recent)
answer with out edit :Use row_number () over (order by ) clause and put some *dummy
select ROW_NUMBER()over(order by (select1) ) as renk ,* from table
answer after edit in question..
select ROW_NUMBER()over(order by timestamp desc ) as renk ,* from table
Hi try this in mysql
SET #rank=0;
SELECT t.rank FROM
(SELECT #rank:=#rank+1 AS rank, id
FROM `table_name`
ORDER BY timestamp DESC) t WHERE t.id=5;
selct * from table where id>1 order by id asc limit 1
if( not date ){
selct * from table where id>0 order by id asc limit 1
}
This question already has answers here:
Implement paging (skip / take) functionality with this query
(6 answers)
Closed 1 year ago.
I have this query with MySQL:
select * from table1 LIMIT 10,20
How can I do this with SQL Server?
Starting SQL SERVER 2005, you can do this...
USE AdventureWorks;
GO
WITH OrderedOrders AS
(
SELECT SalesOrderID, OrderDate,
ROW_NUMBER() OVER (ORDER BY OrderDate) AS 'RowNumber'
FROM Sales.SalesOrderHeader
)
SELECT *
FROM OrderedOrders
WHERE RowNumber BETWEEN 10 AND 20;
or something like this for 2000 and below versions...
SELECT TOP 10 * FROM (SELECT TOP 20 FROM Table ORDER BY Id) ORDER BY Id DESC
Starting with SQL SERVER 2012, you can use the OFFSET FETCH Clause:
USE AdventureWorks;
GO
SELECT SalesOrderID, OrderDate
FROM Sales.SalesOrderHeader
ORDER BY SalesOrderID
OFFSET 10 ROWS
FETCH NEXT 10 ROWS ONLY;
GO
http://msdn.microsoft.com/en-us/library/ms188385(v=sql.110).aspx
This may not work correctly when the order by is not unique.
If the query is modified to ORDER BY OrderDate, the result set returned is not as expected.
This is how I limit the results in MS SQL Server 2012:
SELECT *
FROM table1
ORDER BY columnName
OFFSET 10 ROWS FETCH NEXT 10 ROWS ONLY
NOTE: OFFSET can only be used with or in tandem to ORDER BY.
To explain the code line OFFSET xx ROWS FETCH NEXT yy ROW ONLY
The xx is the record/row number you want to start pulling from in the table, i.e: If there are 40 records in table 1, the code above will start pulling from row 10.
The yy is the number of records/rows you want to pull from the table.
To build on the previous example: If table 1 has 40 records and you began pulling from row 10 and grab the NEXT set of 10 (yy).
That would mean, the code above will pull the records from table 1 starting at row 10 and ending at 20. Thus pulling rows 10 - 20.
Check out the link for more info on OFFSET
This is almost a duplicate of a question I asked in October:
Emulate MySQL LIMIT clause in Microsoft SQL Server 2000
If you're using Microsoft SQL Server 2000, there is no good solution. Most people have to resort to capturing the result of the query in a temporary table with a IDENTITY primary key. Then query against the primary key column using a BETWEEN condition.
If you're using Microsoft SQL Server 2005 or later, you have a ROW_NUMBER() function, so you can get the same result but avoid the temporary table.
SELECT t1.*
FROM (
SELECT ROW_NUMBER OVER(ORDER BY id) AS row, t1.*
FROM ( ...original SQL query... ) t1
) t2
WHERE t2.row BETWEEN #offset+1 AND #offset+#count;
You can also write this as a common table expression as shown in #Leon Tayson's answer.
SELECT *
FROM (
SELECT TOP 20
t.*, ROW_NUMBER() OVER (ORDER BY field1) AS rn
FROM table1 t
ORDER BY
field1
) t
WHERE rn > 10
Syntactically MySQL LIMIT query is something like this:
SELECT * FROM table LIMIT OFFSET, ROW_COUNT
This can be translated into Microsoft SQL Server like
SELECT * FROM
(
SELECT TOP #{OFFSET+ROW_COUNT} *, ROW_NUMBER() OVER (ORDER BY (SELECT 1)) AS rnum
FROM table
) a
WHERE rnum > OFFSET
Now your query select * from table1 LIMIT 10,20 will be like this:
SELECT * FROM
(
SELECT TOP 30 *, ROW_NUMBER() OVER (ORDER BY (SELECT 1)) AS rnum
FROM table1
) a
WHERE rnum > 10
SELECT TOP 10 * FROM table;
Is the same as
SELECT * FROM table LIMIT 0,10;
Here's an article about implementing Limit in MsSQL Its a nice read, specially the comments.
This is one of the reasons I try to avoid using MS Server... but anyway. Sometimes you just don't have an option (yei! and I have to use an outdated version!!).
My suggestion is to create a virtual table:
From:
SELECT * FROM table
To:
CREATE VIEW v_table AS
SELECT ROW_NUMBER() OVER (ORDER BY table_key) AS row,* FROM table
Then just query:
SELECT * FROM v_table WHERE row BETWEEN 10 AND 20
If fields are added, or removed, "row" is updated automatically.
The main problem with this option is that ORDER BY is fixed. So if you want a different order, you would have to create another view.
UPDATE
There is another problem with this approach: if you try to filter your data, it won't work as expected. For example, if you do:
SELECT * FROM v_table WHERE field = 'test' AND row BETWEEN 10 AND 20
WHERE becomes limited to those data which are in the rows between 10 and 20 (instead of searching the whole dataset and limiting the output).
In SQL there's no LIMIT keyword exists. If you only need a limited number of rows you should use a TOP keyword which is similar to a LIMIT.
Must try. In below query, you can see group by, order by, Skip rows, and limit rows.
select emp_no , sum(salary_amount) from emp_salary
Group by emp_no
ORDER BY emp_no
OFFSET 5 ROWS -- Skip first 5
FETCH NEXT 10 ROWS ONLY; -- limit to retrieve next 10 row after skiping rows
Easy way
MYSQL:
SELECT 'filds' FROM 'table' WHERE 'where' LIMIT 'offset','per_page'
MSSQL:
SELECT 'filds' FROM 'table' WHERE 'where' ORDER BY 'any' OFFSET 'offset'
ROWS FETCH NEXT 'per_page' ROWS ONLY
ORDER BY is mandatory
This is a multi step approach that will work in SQL2000.
-- Create a temp table to hold the data
CREATE TABLE #foo(rowID int identity(1, 1), myOtherColumns)
INSERT INTO #foo (myColumns) SELECT myData order By MyCriteria
Select * FROM #foo where rowID > 10
SELECT
*
FROM
(
SELECT
top 20 -- ($a) number of records to show
*
FROM
(
SELECT
top 29 -- ($b) last record position
*
FROM
table -- replace this for table name (i.e. "Customer")
ORDER BY
2 ASC
) AS tbl1
ORDER BY
2 DESC
) AS tbl2
ORDER BY
2 ASC;
-- Examples:
-- Show 5 records from position 5:
-- $a = 5;
-- $b = (5 + 5) - 1
-- $b = 9;
-- Show 10 records from position 4:
-- $a = 10;
-- $b = (10 + 4) - 1
-- $b = 13;
-- To calculate $b:
-- $b = ($a + position) - 1
-- For the present exercise we need to:
-- Show 20 records from position 10:
-- $a = 20;
-- $b = (20 + 10) - 1
-- $b = 29;
If your ID is unique identifier type or your id in table is not sorted you must do like this below.
select * from
(select ROW_NUMBER() OVER (ORDER BY (select 0)) AS RowNumber,* from table1) a
where a.RowNumber between 2 and 5
The code will be
select * from limit 2,5
better use this in MSSQLExpress 2017.
SELECT * FROM
(
SELECT ROW_NUMBER() OVER (ORDER BY (SELECT 0)) as [Count], * FROM table1
) as a
WHERE [Count] BETWEEN 10 and 20;
--Giving a Column [Count] and assigning every row a unique counting without ordering something then re select again where you can provide your limits.. :)
One of the possible way to get result as below , hope this will help.
declare #start int
declare #end int
SET #start = '5000'; -- 0 , 5000 ,
SET #end = '10000'; -- 5001, 10001
SELECT * FROM (
SELECT TABLE_NAME,TABLE_TYPE, ROW_NUMBER() OVER (ORDER BY TABLE_NAME) as row FROM information_schema.tables
) a WHERE a.row > #start and a.row <= #end
If i remember correctly (it's been a while since i dabbed with SQL Server) you may be able to use something like this: (2005 and up)
SELECT
*
,ROW_NUMBER() OVER(ORDER BY SomeFields) AS [RowNum]
FROM SomeTable
WHERE RowNum BETWEEN 10 AND 20
This is my problem.
table ns_leagues:
id name
1 League 1
2 League 2
3 League 3
table ns_upcoming:
upID league date
1 1 1410390000
2 2 1411990200
3 3 1412010000
I have this 2 columns and I want to select the leagues from table ns_leagues and order by the row from the ns_upcoming with the date more close to the current time.
I tried several ways but nothings is working so far.
FAIL:
SELECT id
FROM ns_leagues
WHERE id in (
SELECT league
FROM ns_upcoming
WHERE date<='".$now."'
ORDER BY date ASC
SELECT DISTINCT id
from ns_leagues a
LEFT JOIN ns_upcoming v ON a.id = v.league AND v.date<= '".$now."'
ORDER BY v.date ASC
CURRENT:
SELECT * FROM ".PREFIX."leagues ORDER BY id DESC
This is what I have right now (on the right side: PROXIMOS PARTIDOS): http://www.nuno-silva.pt/jobs/mark/index.php
"En vivo" means that date >= time(); and it's not finished.
The times are countdowns for the match.
I need to order the leagues by date (selecting for that the row with the closest date to time(); from column date of table ns_upcoming of the selected league)
Could you give me a help on this one please?
You'd need to sort by the time DIFFERENCE between "now" and the match's time, e.g.
SELECT ...
...
ORDER BY DATEDIFF(ns_upcoming.date, curdate())
Say i have a table Guest and it has column g_id : values 1 to 10.
Now i want the query to return me the g_id's neither in ascending order nor in descending..
but i want the 4th then 3rd and then 5th entry, in this particular order.
Also i want just the 4th 3rd and 5th entry.
say my entries have an id and a name . ;i.e. my table Guest has these two tables.
Now my table is as following.
1 A
2 B
3 C
4 D
5 E
6 F
7 G
8 H
9 I
10 J
Now i want just the entry with 4th 3rd and 5th g_id, and in this particular order.
How do i write the SQL query?
Thanks.
Select * from Guest ___________???
Kindly fill in the gaps.
You can use a CASE statement in your ORDER BY to use a fake column to sort on and a WHERE IN clause to only return the values you need.
SELECT *
FROM Guest
WHERE g_id IN (3, 4, 5)
ORDER BY
CASE WHEN g_id = 4 THEN 1
WHEN g_id = 3 THEN 2
WHEN g_id = 5 THEN 3
END
What is the order that deteremines whether something is 4th, 3rd or 5th? Without an ORDER BY clause, the data is returned in an indeterminate order by SQL. You cannot rely on the order that rows are entered or stored in the database table itself.
You can hard-code what you are asking like this:
select *
from Guest
order by case
when g_id = 4 then 1
when g_id = 3 then 2
when g_id = 5 then 3
else 4
end
One solution is the case statement:
select g_id from (
select g_id, case g_id
when 4 then 1
when 3 then 2
when 5 then 3
else 0
end virtcol
where virtcol != 0
order by virtcol
);
I'm not sure how set your ordering will be, but you can order by specifics:
ORDER BY
g_id = 4 DESC,
g_id = 3 DESC,
g_id = 5 DESC
You may be better off selecting the entries as they are and doing something like this in your php code:
$order = array('4 ', '3 ', '5 ');
$data = array();
while ($row = $result->fetch()) {
$data["$row->g_id "] = $row;
}
$data = array_merge(array_flip($order), $data);
I think that the answer mostly depends on the DBMS you are working on.
In Oracle the query below, even though inefficient, should work
select * from
(select * , rownum as order from guest order by id asc ) b
where b.order = 4
UNION
select * from
(select * , rownum as order from guest order by id asc ) b
where b.order = 3
UNION
select * from
(select * , rownum as order from guest order by id asc ) b
where b.order = 5
Not sure if something of more efficient is possible with a simple query,
i would use the monster above only and only if the table you are querying is very small.
You also have another option if the table is big and you have to extract only the first rows. In the case you described, I would retrieve the first 5 rows and then programmatically I would extract the rows in position 4,3,5.
you can extract the first 5 rows with this query in oracle
select * from guest order by id asc where rownum < 6
This query will get you the 3rd, 5th, and 4th items (limit 2, 1 means "retrieve starting with 3rd item, with total number retrieved = 1 records)
(select g_id from Guest limit 2,1)
UNION (select g_id from Guest limit 4,1
UNION (select g_id from Guest limit 3,1)