Is there any way to add some line numbers in the result grid in MySQL Workbench?
E.g. (red numbers):
I don't want to have to change the SQL query, which I know I can do using tricks like
SELECT #n := #n + 1 `Number of Submissions`, t.*
FROM (SELECT #n:=0) initvars,
( SELECT COUNT(*) AS count
FROM moocdb.submissions
GROUP BY user_id
ORDER BY count DESC
) t
I also don't want to have to export the results.
Not sure if that is a good question for SO, but anyway: no this is not possible. Nobody asked for that so far, so, file a feature request at http://bugs.mysql.com to have that in.
MySQL does not provide row_number like Microsoft SQL Server, Oracle, or PostgreSQL. Fortunately, MySQL provides session variables that you can use to emulate the row_number function.
SET #row_number = 0;
SELECT (#row_number:=#row_number + 1) AS num, col_1
FROM
Table
Related
Documentation provides an example of using the pivot() function.
SELECT *
FROM (SELECT partname, price FROM part) PIVOT (
AVG(price) FOR partname IN ('prop', 'rudder', 'wing')
);
I would like to use pivot() without having to manually specify each value of partname. I want all parts. I tried:
SELECT *
FROM (SELECT partname, price FROM part) PIVOT (
AVG(price) FOR partname);
That gave an error. Then tried:
SELECT *
FROM (SELECT partname, price FROM part) PIVOT (
AVG(price) FOR partname IN (select distinct partname from part)
);
That also threw an error.
How can I tell Redshift to include all values of partname in the pivot?
I don't think this can be done in a simple single query. This would mean that the query compiler would need to work without knowing how many output columns will be produced. I don't think it can do that.
You can do this in multiple queries - use a query to create the list of partnames and then use this to "generate" a second query that populates the IN list. So something needs issue these queries and generated the second. This can be some code external to Redshift (lots of options) or a stored procedure in Redshift. This code, no matter where it exists, should understand that Redshift has a max number of columns limit - 1,600.
The Redshift docs are fairly good on the topic of dynamic SQL for stored procedures. The EXECUTE statement will be used to fire off the second query in a stored procedure. See: https://docs.aws.amazon.com/redshift/latest/dg/c_PLpgSQL-statements.html
I'm researching a dataset.
And I just wonder if there is a way to order like below in 1 query
Select * From MyTable where name ='international%' order by id
Select * From MyTable where name != 'international%' order by id
So first showing all international items, next by names who dont start with international.
My question is not about adding columns to make this work, or use multiple DB's, or a largerTSQL script to clone a DB into a new order.
I just wonder if anything after 'Where or order by' can be tricked to do this.
You can use expressions in the ORDER BY:
Select * From MyTable
order by
CASE
WHEN name like 'international%' THEN 0
ELSE 1
END,
id
(From your narrative, it also sounded like you wanted like, not =, so I changed that too)
Another way (slightly cleaner and a tiny bit faster)
-- Sample Data
DECLARE #mytable TABLE (id INT IDENTITY, [name] VARCHAR(100));
INSERT #mytable([name])
VALUES('international something' ),('ACME'),('international waffles'),('ABC Co.');
-- solution
SELECT t.*
FROM #mytable AS t
ORDER BY -PATINDEX('international%', t.[name]);
Note too that you can add a persisted computed column for -PATINDEX('international%', t.[name]) to speed things up.
I know in DB2 (using version 9.7) I can select the first 10 rows of a table by using this query:
SELECT *
FROM myTable
ORDER BY id
FETCH FIRST 10 ROWS ONLY
But how can I get, for example, rows 11 to 20?
I can't use the primary key or the ID to help me...
Thanks in advance!
Here's a sample query that will get rows from a table contain state names, abbreviations, etc.
SELECT *
FROM (
SELECT stabr, stname, ROW_NUMBER() OVER(ORDER BY stname) AS rownumber
FROM states
WHERE stcnab = 'US'
) AS xxx
WHERE rownumber BETWEEN 11 AND 20 ORDER BY stname
Edit: ORDER BY is necessary to guarantee that the row numbering is consistent
between executions of the query.
You can also use the MYSQL compatibility. You just need to activate the vector compatibility for MYS, and then use Limit and Offset in your queries.
db2set DB2_COMPATIBILITY_VECTOR=MYS
db2stop
db2start
An excellent article written by DB2 experts from IBM https://www.ibm.com/developerworks/mydeveloperworks/blogs/SQLTips4DB2LUW/entry/limit_offset?lang=en
Compatibility vector in InfoCenter http://publib.boulder.ibm.com/infocenter/db2luw/v10r1/topic/com.ibm.db2.luw.apdv.porting.doc/doc/r0052867.html
A blog about this http://victorsergienko.com/db2-supports-limit-and-offset/
This is really only a short question, but I can't find the answer anywhere.
Is it possible to use an Excel parameter in a t/sql query as a SELECT TOP xxxx, where the parameter here defines how many rows are fetched, without using a stored procedure?
From sql 2005 and up you can write your query as:
Enter the following in your msquery:
{CALL sp_executesql (N'select top (#a) * from mytable', N'#a int', ?)}
I'm not sure about applying the Excel parameter, but to do this in T-SQL do:
select *
from (
select row_number() over (order by [Field]) as rowNum, *
from [myTable] ) s
where s.rowNum < #maxRows
If you are in Excel can you not use Concat to build up the sql query?
Concatenate("select top ", $D2, " from mytable where...")
and use the value of that cell as your tsql expression?
http://msdn.microsoft.com/en-us/library/aa188518(v=office.10).aspx
I'm working with a Sybase 12.5 server and I have a table defined as such:
CREATE TABLE SomeTable(
[GroupID] [int] NOT NULL,
[DateStamp] [datetime] NOT NULL,
[SomeName] varchar(100),
PRIMARY KEY CLUSTERED (GroupID,DateStamp)
)
I want to be able to list, per [GroupID], only the latest X records by [DateStamp]. The kicker is X > 1, so plain old MAX() won't cut it. I'm assuming there's a wonderfully nasty way to do this with cursors and what-not, but I'm wondering if there is a simpler way without that stuff.
I know I'm missing something blatantly obvious and I'm gonna kick myself for not getting it, but .... I'm not getting it. Please help.
Is there a way to find TOP X records, but with grouped data?
According to the online manual, Sybase 12.5 supports WINDOW functions and ROW_NUMBER(), though their syntax differs from standard SQL slightly.
Try something like this:
SELECT SP.*
FROM (
SELECT *, ROW_NUMBER() OVER (windowA ORDER BY [DateStamp] DESC) AS RowNum
FROM SomeTable
WINDOW windowA AS (PARTITION BY [GroupID])
) AS SP
WHERE SP.RowNum <= 3
ORDER BY RowNum DESC;
I don't have an instance of Sybase, so I haven't tested this. I'm just synthesizing this example from the doc.
I made a mistake. The doc I was looking at was Sybase SQL Anywhere 11. It seems that Sybase ASA does not support the WINDOW clause at all, even in the most recent version.
Here's another query that could accomplish the same thing. You can use a self-join to match each row of SomeTable to all rows with the same GroupID and a later DateStamp. If there are three or fewer later rows, then we've got one of the top three.
SELECT s1.[GroupID], s1.[Foo], s1.[Bar], s1.[Baz]
FROM SomeTable s1
LEFT OUTER JOIN SomeTable s2
ON s1.[GroupID] = s2.[GroupID] AND s1.[DateStamp] < s2.[DateStamp]
GROUP BY s1.[GroupID], s1.[Foo], s1.[Bar], s1.[Baz]
HAVING COUNT(*) < 3
ORDER BY s1.[DateStamp] DESC;
Note that you must list the same columns in the SELECT list as you list in the GROUP BY clause. Basically, all columns from s1 that you want this query to return.
Here's quite an unscalable way!
SELECT GroupID, DateStamp, SomeName
FROM SomeTable ST1
WHERE X <
(SELECT COUNT(*)
FROM SomeTable ST2
WHERE ST1.GroupID=ST2.GroupID AND ST2.DateStamp > ST1.DateStamp)
Edit Bill's solution is vastly preferable though.