Is there a way to define an identity column on another column? What I want to accomplish is a table that holds positions of an order and these orders can be put there anytime. So it could be that there are already lets say three positions in the table and it would look somewhat like this:
OrderNumber | OrderPosition
10001 1
10001 2
10001 3
And now I want to add another position without calculating the right value for the OrderPosition column. This is because I want to write new positions for multiple orders into the table and would like to avoid cursoring over the individual orders. I would prefer a solution wher OrderPosition is an identity column that is reseeded based on the OrderNumber column. So that If i add an order position for a new order it would start with 1 and if I add another position for order 10001 it would continue with 4.
Write a Scalar Function that returns the MAX(OrderPosition) based on OrderNumber. Then reference that function in the insert statement of orders
your requirement will not work for identity column.
You need to create custom logic to get from the normal columns and on combination based new no will generate.. like (read comments, only choose one logic)
declare #t table(OrderNumber int, OrderPosition int)
insert into #t values (10001, 1),(10001, 2),(10001, 3),(10001, 4)
select * from #t
--now insert new record with old orderno
declare #seq int = 1
declare #ordernumberNew int = 10001
--Eigher you can use :- insert to more understand
if( exists(select orderposition from #t where OrderNumber = #ordernumberNew ))
begin
set #seq = (select max(OrderPosition) + 1 from #t where OrderNumber = #ordernumberNew )
end
insert into #t values (#ordernumberNew , #seq )
select * from #t
--or another twist of above statement, insert directly as
insert into #t
values
(
#ordernumberNew,
case when exists (select orderposition from #t where OrderNumber = #ordernumberNew )
then (select max(OrderPosition) + 1 from #t where OrderNumber = #ordernumberNew )
else 1 end
)
select * from #t
--Now enter the not exist order no
set #ordernumberNew = 10006
insert into #t
values
(
#ordernumberNew,
case when exists (select orderposition from #t where OrderNumber = #ordernumberNew )
then (select max(OrderPosition) + 1 from #t where OrderNumber = #ordernumberNew )
else 1 end
)
select * from #t
Related
I need to find the most occurrences in a 10yr age range that can be Age 2 to 22, 15 to 25, 10 to 20, etc. in a table with name & age
I've created the SQL that returns the average age:
SELECT age, count(age)
FROM member
GROUP BY age
ORDER BY COUNT(age) DESC
LIMIT 1
Thanks for your help!
Create another table ages to hold the age ranges you are interested in with a field for age_lower, age_upper and a display name age_range such as '2 to 22'
Join the tables with a WHERE clause that puts the age between the lower and upper ranges.
SELECT `age_range`, COUNT(`age`) AS age_count
FROM `member` INNER JOIN `ages`
ON age BETWEEN age_lower AND age_upper
GROUP BY age_range
ORDER BY COUNT(`age`) DESC, `age_range` ASC
SQL Fiddle
This might solve the problem. The only thing I added was a table to hold values 1..x where x is your bucket count. The #T can easily be replaced with your MySQL table name. The results are all possible sets the age falls in, for each age. Then count of how many equal sets.
--IGNORE BUILDING TEST DATA IN SQL SERVER
DECLARE #T TABLE(member INT,age INT)
DECLARE #X INT
SET #X=1
WHILE(#X<=100) BEGIN
INSERT INTO #T SELECT #X, CAST(RAND() * 100 AS INT)
SET #X=#X+1
END
DECLARE #MinAge INT=1
DECLARE #MaxAge INT=100
--YOUR SET TABLE. TO MAKE LIFE EASY YOU NEED A TABLE OF 1..X
DECLARE #SET TABLE (Value INT)
DECLARE #SET_COUNT INT =10
DECLARE #LOOP INT=1
WHILE(#LOOP<=#SET_COUNT) BEGIN
INSERT #SET SELECT #LOOP
SET #LOOP=#LOOP+1
END
SELECT
MinAge,
MaxAge,
SetCount=COUNT(CountFlag)
FROM
(
SELECT
MinAge=AgeMinusSetCount,
MaxAge=AgePlusSetCount,
CountFlag=1
FROM
(
SELECT DISTINCT
ThisAge,
AgeMinusSetCount=(AgeMinusSetCount-1) + Value,
AgePlusSetCount=CASE WHEN (AgeMinusSetCount-1) + Value + #SET_COUNT > #MaxAge THEN #MaxAge ELSE (AgeMinusSetCount-1) + Value + #SET_COUNT END
FROM
(
SELECT
ThisAge=age,
AgeMinusSetCount=CASE WHEN (age - #SET_COUNT) < #MinAge THEN #MinAge ELSE (age) - #SET_COUNT END
FROM
#T
)RANGES
LEFT OUTER JOIN (SELECT Value FROM #SET) AS FanLeft ON 1=1
)AS DETAIL
)AS Summary
GROUP BY
MinAge,
MaxAge
ORDER BY
COUNT(CountFlag) DESC
I need to make trigger to increase the 2nd digit when the new value found to be a duplicate.
For Instance, I have a unique filed with 10 digits value. I want when someone insert same number it increase the second left digit like 0100012345. How I can do that? Thank you.
FirstName LastName Code
Houssam Salim 0100012345 to be 0200012345
Try this
I have found a solution with instead off trigger
'/*
CREATE TABLE [Employee1]
(
[id] VARCHAR(20) PRIMARY KEY,
[name] VARCHAR(50)
)
CREATE TRIGGER AutoIncrement_Trigger
ON [Employee1]
instead OF INSERT
AS
BEGIN
DECLARE #ch CHAR
DECLARE #num INT
IF EXISTS (SELECT 1
FROM Employee1 e
JOIN inserted i
ON i.id = e.id)
BEGIN
SET #num=(SELECT max(CONVERT(INT, substring(e.id, 1, 2))) + 1
FROM employee1 e
JOIN inserted i
ON substring(e.id, 3, len(e.id)) = substring(i.id, 3, len(i.id)))
INSERT INTO [Employee1]
(id,
name)
SELECT '0' + CONVERT(VARCHAR(10), #num)
+ substring(i.id, 3, len(i.id)),
e.name
FROM Employee1 e
JOIN inserted i
ON i.id = e.id
END
ELSE
BEGIN
INSERT INTO [Employee1]
(id,
name)
SELECT inserted.id,
inserted.name
FROM inserted
END
END
*/
INSERT INTO [Employee1]
VALUES ('0100012345',
'John')
SELECT *
FROM [Employee1]
INSERT INTO [Employee1]
VALUES ('0100012345',
'John')
SELECT *
FROM [Employee1]
'
I want a query to insert a row into a table I know it is simple but the scenario is the table should not have more than 5 rows. If table has more than five rows I need to remove the old row(Or replace with new row ) (Based on the insert time stamp) then i need to insert a new row.If number of rows less than count 5 then i can directly insert a row.
Please share me the query.
How about something like this.
declare #count int
SELECT #count=COUNT(*)
from EP_ANSWERS
IF (#count<5)
// DO your insert here
ELSE
DELETE FROM TABLE
WHERE inserttimestamp = (SELECT x.inserttimestamp
FROM (SELECT MAX(t.inserttimestamp) AS inserttimestamp
FROM TABLE t) x)
// DO your insert here
If it is impossible for the table to have more than 5 rows:
DELETE FROM yourtable
WHERE 5 <= (SELECT COUNT(*) FROM yourtable)
AND yourtimestamp = (SELECT MIN(yourtimestamp) FROM yourtable)
;
INSERT INTO yourtable ...
;
If it is possible for the table to have more than 5 rows:
DELETE FROM yourtable
WHERE 5 <= (SELECT COUNT(*) FROM yourtable)
AND yourtimestamp NOT IN (SELECT yourtimestamp
FROM yourtable
ORDER BY yourtimestamp DESC
LIMIT 4)
;
INSERT INTO yourtable ...
;
It sounds like you want to put a trigger on the table to maintain this rule, in MySQL the something like this should work
CREATE TRIGGER trg__my_table__limit_rows
BEFORE INSERT
ON my_table
FOR EACH ROW
BEGIN
IF ((SELECT COUNT(1) FROM my_table) = 5)
BEGIN
DELETE FROM my_table
WHERE id = (SELECT MIN(id) FROM my_table) -- change this to fit your logic for which record should be removed
END
END
Some of the code here is in pseudo (you didn't wrote your schema), but i wrote where you need to complete your own code.
DECLARE #NumberOfRowsToInsert INT = -- select from the data you want to insert
DECLARE #MaxNumberOfRows INT = 5
DECLARE #NumberOfExistingRows INT
DECLARE #Query VARCHAR(MAX) = 'SELECT TOP #rows id FROM SomeTable ORDER BY createdDate ASC'
SELECT #NumberOfExistingRows = COUNT(*)
FROM SomeTable
SET #Query = REPLACE(#Query,'#rows',
CAST(#NumberOfRowsToInsert - (#MaxNumberOfRows - #NumberOfExistingRows))) AS VARCHAR(1))
CREATE TABLE #IdsToDelete(id INT PRIMARY KEY)
INSERT INTO #IdsToDelete
EXEC(#Query)
DELETE FROM SomeTable
WHERE id IN (SELECT * FROM #IdsToDelete)
-- insert here..
I have 2 tables, T1 and T2. I want to join these 2 tables and return only 2 rows of data, replacing the integers in Item with their lookup values from T2.
Table T1
Item Date
------ ---------
1;4;5; 3/13/2013
1;2;3; 3/13/2013
Table T2
ID Desc
---- ------
1 Tree
2 Grass
3 Sand
4 Water
5 Bridge
Expected results:
Item Date
------------------ ---------
Tree;Water;Bridge; 3/13/2013
Tree;Grass;Sand; 3/13/2013
First, create a Split function which returns an integer and an order-preserving sequence number. Here is one example:
ALTER FUNCTION dbo.SplitInts
(
#List VARCHAR(MAX),
#Delimiter VARCHAR(32)
)
RETURNS TABLE
AS
RETURN
(
SELECT rn = ROW_NUMBER() OVER (ORDER BY Number),
Item = CONVERT(INT, Item)
FROM (SELECT Number, Item = LTRIM(RTRIM(SUBSTRING(#List, Number,
CHARINDEX(#Delimiter, #List + #Delimiter, Number) - Number)))
FROM (SELECT ROW_NUMBER() OVER (ORDER BY [object_id])
FROM sys.all_objects) AS n(Number)
WHERE Number <= CONVERT(INT, LEN(#List))
AND SUBSTRING(#Delimiter + #List, Number, 1) = #Delimiter
) AS y
);
GO
Then the following query does what you're after:
DECLARE #t1 TABLE
(
Item VARCHAR(MAX),
[Date] DATE -- terrible column name!
);
INSERT #t1 VALUES('1;4;5;','20130313'),('1;2;3;','20130313');
-- please use unambiguous date formats!
DECLARE #t2 TABLE
(
ID INT, -- another bad column name - what kind of ID?
[Desc] VARCHAR(255) -- another bad column name, this is a keyword!
);
INSERT #t2 VALUES(1,'Tree'),(2,'Grass'),
(3,'Sand'),(4,'Water'),(5,'Bridge');
;WITH x AS
(
SELECT t1.Item, Date, t2ID = i.Item, i.rn, n = t2.[Desc]
FROM #t1 AS t1 CROSS APPLY dbo.SplitInts(t1.Item, ';') AS i
INNER JOIN #t2 AS t2 ON i.Item = t2.ID
)
SELECT DISTINCT Item = (
SELECT n + ';' FROM x AS x2
WHERE x.Item = x2.Item
ORDER BY x2.rn FOR XML PATH,
TYPE).value(N'./type()[1]', N'varchar(max)'), [Date]
FROM x;
Strongly recommend you research normalization. A semi-colon-separated list is a terrible way to cram together independent values.
Let suppose my table can have values from 000 to 999 (three digits and less than 1000)
Some of this values are filled. Let's suppose currently my table has
000,002,005,190 (001,004,003,006,..189,191,..,999 can be inserted into table)
and these values are randomly allocated 000 and 002 is in table but 001 is not in table yet.
How can I get the values that I can insert into table yet.
DECLARE #t TABLE
(VALUE CHAR(3))
INSERT #t
VALUES
('000'),('002'),('005'),('190')
;WITH rnCTE
AS
(
SELECT -1 + ROW_NUMBER() OVER (ORDER BY TYPE, number, name) AS rn
FROM master.dbo.spt_values
)
SELECT RIGHT('000' + CAST( rn AS VARCHAR(11)),3)
FROM rnCTE
WHERE NOT EXISTS ( SELECT 1 FROM #t
WHERE VALUE = rn
)
AND rn < 1000
EDIT
This query works by generating the complete list of possible numbers from a system table (master.dbo.spt_values) which is guaranteed to contain more than 1000 rows inside the CTE rnCTE. -1 is added to ROW_NUMBER to have the values start at 0 rather than 1.
The outer query zero pads the numbers for display, returning only those which are not in the source data and are less than 1000.
DECLARE #t TABLE(id INT)
INSERT INTO #t (id)
VALUES
(1),(19),(3)
;WITH numbers AS (
SELECT ROW_NUMBER() OVER(ORDER BY o.object_id,o2.object_id) RN FROM sys.objects o
CROSS JOIN sys.objects o2
), NotExisted AS(
SELECT * FROM numbers WHERE RN NOT IN (SELECT ID FROM #t)
AND RN<1000)
SELECT TOP 1 RN FROM NotExisted ORDER BY NEWID()
You will have to write a T-SQL to first query and find the gaps. There is no ready made SQL that will give you the gaps directly.