How can i sort my data by the last digit. I'm trying to sort a list of locations that look like AQ045A, the last digit being the height level.
So the data is a series of locations
AG045A,
AN045B,
AG046B,
AG046C,
SELECT STOLOC
FROM locmst_view
WHERE wh_id = 'US_3278'
AND locsts = 'E'
AND useflg = 1
AND sto_zone_cod LIKE '%FCC%'
ORDER BY right(STOLOC, 1),
STOLOC
Related
I've the following data.
What I need like below
I need to minus order by 1 with 2.
Example : (1-2) and I've display the result in order by 3.
If the branch having order_by as 1 - display as it is.
Using MySQL, how can I get this result?
You can get this result with a UNION query. The first part selects all rows from your table, the second uses a self-join to find branches which have order_by values of both 1 and 2, and subtracts their due values to get the new due value:
SELECT *
FROM data
UNION ALL
SELECT 3, d1.branch, d1.due - d2.due
FROM data d1
JOIN data d2 ON d2.branch = d1.branch AND d2.order_by = 2
WHERE d1.order_by = 1
ORDER BY branch, order_by
Demo on dbfiddle
I am thinking of having a top 7 list of items.
So, linked lists pop in my head because the new high ranking item will be added, or promoted from lower rank, to push down the lower ranking items by one step. The way I need it be.
I would just need to access the top 7 (a chosen number) of object according to the ranks.
How should I store it in a database? Or should I store it in file storage? I could just add some item or write cut/paste type codes for the already ranked item, but unfortunately that's not how my db (MYSQL) works. So, any suggestions?
Think about the UI for adding a "new number 3". This implies bumping everything 3 and greater by one.
So... You have a column that is the rank. The SQL is
UPDATE MyList SET rank = rank + 1 WHERE rank >= 3;
INSERT INTO MyList (rank, ...)
VALUES (3, ...);
Getting the top 7:
SELECT * FROM MyList WHERE rank <= 7 ORDER BY rank;
To "move" the current rank 12 item to rank 5, there are many approaches. Here is one:
UPDATE MyList SET rank = -1 WHERE rank = 12;
UPDATE MyList SET rank = rank + 1 WHERE rank BETWEEN 5 AND 12;
UPDATE MyList SET rank = 5 WHERE rank = -1;
I am trying to find a reliable query which returns the first instance of an acceptable insert range.
Research:
some of the below links adress similar questions, but I could get none of them to work for me.
Find first available date, given a date range in SQL
Find closest date in SQL Server
MySQL difference between two rows of a SELECT Statement
How to find a gap in range in SQL
and more...
Objective Query Function:
InsertRange(1) = (StartRange(i) - EndRange(i-1)) > NewValue
Where InsertRange(1) is the value the query should return. In other words, this would be the first instance where the above condition is satisfied.
Table Structure:
Primary Key: StartRange
StartRange(i-1) < StartRange(i)
StartRange(i-1) + EndRange(i-1) < StartRange(i)
Example Dataset
Below is an example User table (3 columns), with a set range distribution. StartRanges are always ordered in a strictly ascending way, UserID are arbitrary strings, only the sequences of StartRange and EndRange matters:
StartRange EndRange UserID
312 6896 user0
7134 16268 user1
16877 22451 user2
23137 25142 user3
25955 28272 user4
28313 35172 user5
35593 38007 user6
38319 38495 user7
38565 45200 user8
46136 48007 user9
My current Query
I am trying to use this query at the moment:
SELECT t2.StartRange, t2.EndRange
FROM user AS t1, user AS t2
WHERE (t1.StartRange - t2.StartRange+1) > NewValue
ORDER BY t1.EndRange
LIMIT 1
Example Case
Given the table, if NewValue = 800, then the returned answer should be 23137. This means, the first available slot would be between user3 and user4 (with an actual slot size = 813):
InsertRange(1) = (StartRange(i) - EndRange(i-1)) > NewValue
InsertRange = (StartRange(6) - EndRange(5)) > NewValue
23137 = 25955 - 25142 > 800
More Comments
My query above seemed to be working for the special case where StartRanges where tightly packed (i.e. StartRange(i) = StartRange(i-1) + EndRange(i-1) + 1). This no longer works with a less tightly packed set of StartRanges
Keep in mind that SQL tables have no implicit row order. It seems fair to order your table by StartRange value, though.
We can start to solve this by writing a query to obtain each row paired with the row preceding it. In MySQL, it's hard to do this beautifully because it lacks the row numbering function.
This works (http://sqlfiddle.com/#!9/4437c0/7/0). It may have nasty performance because it generates O(n^2) intermediate rows. There's no row for user0; it can't be paired with any preceding row because there is none.
select MAX(a.StartRange) SA, MAX(a.EndRange) EA,
b.StartRange SB, b.EndRange EB , b.UserID
from user a
join user b ON a.EndRange <= b.StartRange
group by b.StartRange, b.EndRange, b.UserID
Then, you can use that as a subquery, and apply your conditions, which are
gap >= 800
first matching row (lowest StartRange value) ORDER BY SB
just one LIMIT 1
Here's the query (http://sqlfiddle.com/#!9/4437c0/11/0)
SELECT SB-EA Gap,
EA+1 Beginning_of_gap, SB-1 Ending_of_gap,
UserId UserID_after_gap
FROM (
select MAX(a.StartRange) SA, MAX(a.EndRange) EA,
b.StartRange SB, b.EndRange EB , b.UserID
from user a
join user b ON a.EndRange <= b.StartRange
group by b.StartRange, b.EndRange, b.UserID
) pairs
WHERE SB-EA >= 800
ORDER BY SB
LIMIT 1
Notice that you may actually want the smallest matching gap instead of the first matching gap. That's called best fit, rather than first fit. To get that you use ORDER BY SB-EA instead.
Edit: There is another way to use MySQL to join adjacent rows, that doesn't have the O(n^2) performance issue. It involves employing user variables to simulate a row_number() function. The query involved is a hairball (that's a technical term). It's described in the third alternative of the answer to this question. How do I pair rows together in MYSQL?
I am using a MySql table with 500,000 records. The table contains a field (abbrevName) which stores a two-character representation of the first two letters on another field, name.
For example AA AB AC and so on.
What I want to achieve is the set the value of another field (pgNo) which stores a value for page number, based on the value of that records abbrevName.
So a record with an abbrevName of 'AA' might get a page number of 1, 'AB' might get a page number of 2, and so on.
The catch is that although multiple records may have the same page number (after all multiple entities might have a name beginning with 'AA'), once the amount of records with the same page number reaches 250, the page number must increment by one. So after 250 'AA' records with a page number of 1, we must assign futher 'AA records with a page number of 2, and so on.
My Pseudocode looks something like this:
-Count distinct abbrevNames
-Count distinct abbrevNames with more than 250 records
-For the above abbrevNames count the the sum of each divided by 250
-Output a temporary table sorted by abbrevName
-Use the total number of distinct page numbers with 250 or less records to assign page numbers incrementally
I am really struggling to put anything together in a query that comes close to this, can anyone help with my logic or some code ?
Please have a try with this one:
SELECT abbrevNames, CAST(pagenumber AS signed) as pagenumber FROM (
SELECT
abbrevNames
, IF(#prev = abbrevNames, #rows_per_abbrev:=#rows_per_abbrev + 1, #pagenr:=#pagenr + 1)
, #prev:=abbrevNames
, IF(#rows_per_abbrev % 250 = 0, #pagenr:=#pagenr + 1, #pagenr) AS pagenumber
, IF(#rows_per_abbrev % 250 = 0, #rows_per_abbrev := 1, #rows_per_abbrev)
FROM
yourTable
, (SELECT #pagenr:=0, #prev:=NULL, #rows_per_abbrev:=0) variables_initialization
ORDER BY abbrevNames
) subquery_alias
UPDATE: I had misunderstood the question a bit. Now it should work
I'm having trouble with this SQL:
$sql = mysql_query("SELECT $menucompare ,
(COUNT($menucompare ) * 100 / (SELECT COUNT( $menucompare )
FROM data WHERE $ww = $button )) AS percentday FROM data WHERE $ww >0 ");
$menucompare is table fields names what ever field is selected and contains data bellow
$button is the week number selected (lets say week '6')
$ww table field name with row who have the number of week '6'
For example, I have data in $menucompare like that:
123456bool
521478bool
122555heel
147788itoo
and I want to select those, who have same word in the last of the data and make percentage.
The output should be like that:
bool -- 50% (2 entries)
heel -- 25% (1 entry)
itoo -- 25% (1 entry)
Any clearness to my SQL will be very appreciated.
I didn't find anything like that around.
Well, keeping data in such format probably not the best way, if possible, split the field into 2 separate ones.
First, you need to extract the string part from the end of the field.
if the length of the string / numeric parts is fixed, then it's quite easy;
if not, you should use regular expressions which, unfortunately, are not there by default with MySQL. There's a solution, check this question: How to do a regular expression replace in MySQL?
I'll assume, that numeric part is fixed:
SELECT s.str, CAST(count(s.str) AS decimal) / t.cnt * 100 AS pct
FROM (SELECT substr(entry, 7) AS str FROM data) AS s
JOIN (SELECT count(*) AS cnt FROM data) AS t ON 1=1
GROUP BY s.str, t.cnt;
If you'll have regexp_replace function, then substr(entry, 7) should be replaced to regexp_replace(entry, '^[0-9]*', '') to achieve the required result.
Variant with substr can be tested here.
When sorting out problems like this, I would do it in two steps:
Sort out the SQL independently of the presentation language (PHP?).
Sort out the parameterization of the query and the presentation of the results after you know you've got the correct query.
Since this question is tagged 'SQL', I'm only going to address the first question.
The first step is to unclutter the query:
SELECT menucompare,
(COUNT(menucompare) * 100 / (SELECT COUNT(menucompare) FROM data WHERE ww = 6))
AS percentday
FROM data
WHERE ww > 0;
This removes the $ signs from most of the variable bits, and substitutes 6 for the button value. That makes it a bit easier to understand.
Your desired output seems to need the last four characters of the string held in menucompare for grouping and counting purposes.
The data to be aggregated would be selected by:
SELECT SUBSTR(MenuCompare, -4) AS Last4
FROM Data
WHERE ww = 6
The divisor in the percentage is the count of such rows, but the sub-stringing isn't necessary to count them, so we can write:
SELECT COUNT(*) FROM Data WHERE ww = 6
This is exactly what you have anyway.
The divdend in the percentage will be the group count of each substring.
SELECT Last4, COUNT(Last4) * 100.0 / (SELECT COUNT(*) FROM Data WHERE ww = 6)
FROM (SELECT SUBSTR(MenuCompare, -4) AS Last4
FROM Data
WHERE ww = 6
) AS Week6
GROUP BY Last4
ORDER BY Last4;
When you've demonstrated that this works, you can re-parameterize the query and deal with the presentation of the results.