I want to get a particular user_id and balance using a SELECT statement with a WHERE clause from user input
This is my trigger in SQL Server 2008:
create trigger trig_trans
on user_accnt after update
as
begin
declare #id int
declare #balance int
declare #transdate date
select #id = user_id, #balance = user_bal
from user_accnt
merge user_trans target
using user_accnt source on target.user_id = source.user_id
when matched then
update set trans_date = getdate(),
balance = #balance
when not matched then
insert (user_id, trans_date, balance)
values(#id, getdate(), #balance);
end
In this SELECT statement, I want to use a WHERE clause.
select #id = user_id, #balance = user_bal
from user_accnt
For example : if I am using
select #id = user_id, #balance = user_bal
from user_accnt
where account_num = 123456
I will get the result.
But in my situation my query should get the account_num from the user input.
Is there any way to do this?
Related
I have a routine. But it' s too slow. How can I improve the query?
My records: http://www.sqlfiddle.com/#!9/14cceb/1/0
My query:
CREATE DEFINER = 'root'#'localhost'
PROCEDURE example.ssa()
BEGIN
drop table if exists gps_table;
drop table if exists exam_datas;
CREATE TEMPORARY TABLE gps_table(ID int PRIMARY KEY AUTO_INCREMENT,timei
int,
trun_date_time datetime, tadd_meter int, tin_here int null);
insert into gps_table(timei,trun_date_time,tadd_meter,tin_here) select
imei, run_date_time, add_meter, in_here from example_table;
CREATE TEMPORARY TABLE exam_datas(ID int PRIMARY KEY AUTO_INCREMENT,vimei
int, vbas_run_date_time datetime, vbit_run_date_time datetime, vdifff int);
select tin_here from gps_table limit 1 into #onceki_durum;
select count(id) from gps_table into #kayit_sayisi;
set #i = 1;
set #min_mes = 0;
set #max_mes = 0;
set #frst_id = 0;
set #imei = 0;
set #run_date_time = '0000-00-00 00:00:00';
set #run_date_time2 = '0000-00-00 00:00:00';
myloop: WHILE (#i <= #kayit_sayisi) DO
select tin_here from gps_table where id = #i into #in_here_true;
if (#in_here_true = 1) then
select id,trun_date_time, tadd_meter from gps_table where id = #i into #frst_id,#run_date_time2, #min_mes;
select id from gps_table where id > #frst_id and tin_here =0 order by id asc limit 1 INTO #id;
SET #id = #id-1;
select id, timei, trun_date_time, tadd_meter from gps_table
where id = #id and tin_here =1 limit 1 into #i, #imei, #run_date_time, #max_mes;
if(#i-#frst_id>3) then
set #i:=#i+1;
insert into exam_datas(vimei,vbas_run_date_time,vbit_run_date_time,vdifff) Values (#imei, #run_date_time2, #run_date_time, #max_mes-#min_mes);
SELECT * FROM exam_datas;
SET #asd =1;
elseif 1=1 then
set #i:=#i+1;
End if;
ELSEIF 1=1
THEN SET #i:=#i+1;
End if;
IF (#i = #kayit_sayisi)
THEN set #tamam =1; LEAVE myloop;
END IF;
END WHILE myloop;
select DISTINCT * from exam_datas;
drop table if exists exam_datas;
drop table if exists gps_table;
END
I need: id= 6 first true and id= 11 last_true
firs_trure - last_true = 304-290= 14
id=14 first true and id=18 last_true
firs_true - last_true = 332-324= 8
This routine is too slow.
MySql version is 5.7 and There are 2 milions record in the table.
UPDATE:
Query is here. HERE
Thank you #LukStorms
It's possible to get such results in 1 query.
Thus avoiding a WHILE loop over records.
This example works without using window functions. Just using variables inside the query to calculate a rank. Which is then used to get the minimums and maximums of the groups.
select
imei,
min(run_date_time) as start_dt,
max(run_date_time) as stop_dt,
max(add_meter) - min(add_meter) as diff
from
(
select imei, id, run_date_time, add_meter, in_here,
case
when #prev_imei = imei and #prev_ih = in_here then #rnk
when #rnk := #rnk + 1 then #rnk
end as rnk,
#prev_imei := imei as prev_imei,
#prev_ih := in_here as prev_ih
from example_table t
cross join (select #rnk := 0, #prev_ih := null, #prev_imei := null) vars
order by imei, id, run_date_time
) q
where in_here = 1
group by imei, rnk
having count(*) > 4
order by imei, min(id);
In the procedure such query can be used to fill that final temporary table.
A test on db<>fiddle here
I am writing a function that should return a floating value.
BEGIN
DECLARE due_amount DECIMAL(9,2);
SET due_amount = (SELECT due_amount FROM (
SELECT id, MAX(date), due_amount, user_id
FROM lunch_transaction
GROUP BY user_id
HAVING user_id = user) l);
IF due_amount IS NULL THEN
SET due_amount = 0.00;
END IF;
RETURN due_amount;
END
The function only returns value 0.00 even though the value should be something else.
Running only this query :
(SELECT due_amount FROM (
SELECT id, MAX(date), due_amount, user_id
FROM lunch_transaction
GROUP BY user_id
HAVING user_id = user) l);
is giving the correct output though.
How should I set the query's output to the variable?
It is really bad practice to use variable name that can conflict with column names. Also, the subquery seems very unnecessary. I would try something more like this:
BEGIN
DECLARE v_due_amount DECIMAL(9,2);
SELECT v_due_amount := l.due_amount
FROM lunch_transaction l
WHERE l.user_id = in_user; -- I'm guessing `user` is also a parameter
IF v_due_amount IS NULL THEN
SET v_due_amount = 0.00;
END IF;
RETURN v_due_amount;
END;
Your version has an aggregation function in the subquery. This makes no sense, because due_amount is not the argument of an aggregation function. This logic should perhaps be:
SELECT v_due_amount := SUM(l.due_amount)
FROM lunch_transaction l
WHERE l.user_id = in_user; -- I'm guessing `user` is also a variable
I have the following SQL update trigger that works properly:
BEGIN
DECLARE myID INT;
SELECT user_id INTO myID FROM writer WHERE writer_id = NEW.writer_id;
IF (NEW.status_id = 2) THEN
INSERT INTO activity (
user_id,
work_id,
activity,
date_created
) VALUES (
myID,
NEW.work_id,
'confirmed',
now()
);
ELSE
INSERT INTO activity (
user_id,
work_id,
activity,
date_created
) VALUES (
myID,
NEW.work_id,
'modified',
now()
);
END IF;
END
I need to add an additional trigger as the following:
CREATE TRIGGER updateWorkStatus AFTER UPDATE ON writer_split
FOR EACH ROW
BEGIN
UPDATE work a
JOIN writer_split b
ON a.work_id = b.work_id AND a.current_version = b.version
SET a.status_id = 2
WHERE a.work_id NOT IN (
SELECT ab.work_id
FROM (SELECT s.work_id
FROM work w INNER JOIN writer_split s
ON w.work_id = s.work_id AND s.status_id != 2) ab
);
END;
when I run this create script, I am getting a syntax error. Any ideas?
For me i will use UPDATE work as a
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 the query working, just wondering if there is a better way to do this without cursors/loops/php side. I've been a DBA for 5+ years and just came across the := statement. Very cool.
Table (tblPeople) with the person ID and the number of tickets they bought.
PersonId NumTickets
1 3
2 1
3 1
I then want to assign individual tickets to each person in a new table (tblTickets), depending on how many tickets they bought. The TicketId is a key, auto increment column.
TicketId PersonId
100 1
101 1
102 1
103 2
104 3
Here is the code. It loops through the whole tblPeople over and over again incrementing a new calculated column called rowID. Then I filter out the rows based on the number of tickets they bought in the WHERE clause. The problem I see is the subquery is huge, the more people I have, the bigger the subquery gets. Just not sure if there is a better way to write this.
INSERT INTO tblTickets (PersonId)
SELECT PersonId
FROM (
SELECT s.PersonId, s.NumTickets,
#rowID := IF(#lastPersonId = s.PersonId and #lastNumTickets = s.NumTickets, #rowID + 1, 0) AS rowID,
#lastPersonId := s.PersonId,
#lastNumTickets := s.NumTickets
FROM tblPeople m,
(SELECT #rowID := 0, #lastPersonId := 0, #lastNumTickets := 0) t
INNER JOIN tblPeople s
) tbl
WHERE rowID < NumTickets
I'd add a utility table Numbers which contains all the numbers from 1 up to the maximal number of tickets a person may buy. Then you can do something like this:
INSERT INTO tblTickets (PersonId)
SELECT s.PersonId
FROM tblPeople s, Numbers n
WHERE n.number <= s.NumTickets
Following Stored procedure will serve your purpose...
DELIMITER $$
USE <your database name> $$
DROP PROCEDURE IF EXISTS `update_ticket_value2`$$
CREATE PROCEDURE `update_ticket_value2`()
BEGIN
DECLARE index_value INT;
DECLARE loop_variable INT;
SET #KeyValue = 100;
SET #LastPersonID = 0;
SET #TicketNum = 0;
SET #PersonIDToHandle = 0;
SELECT #PersonIDToHandle = PersonID, #TicketNum = NumTickets
FROM tblPeople
WHERE PersonId > #LastPersonID
ORDER BY PersonId
LIMIT 0,1;
WHILE #PersonIDToHandle IS NOT NULL
DO
SET loop_variable = 0;
WHILE(loop_variable < #TicketNum) DO
INSERT INTO tblTickets(TicketId, PersonId) VALUES(#KeyValue + loop_variable, #PersonIDToHandle);
SET loop_variable = loop_variable + 1;
END WHILE;
SET #LastPersonID = #PersonIDToHandle;
SET #PersonIDToHandle = NULL;
SET #KeyValue = #KeyValue + #TicketNum;
SELECT #PersonIDToHandle := PersonID, #TicketNum := NumTickets
FROM tblPeople
WHERE PersonId > #LastPersonID
ORDER BY PersonId
LIMIT 0,1;
END WHILE;
END$$
DELIMITER ;
Call the procedure as:
CALL update_ticket_value2();
Hope it helps...