I have this table
I am trying to get the sum of principal + interest from the last transaction date. Column 4. is the last transaction performed - [No column name] is the transaction date
What I have tried so far:
select sum(h.principal+h.interest) as amt_paid, MAX(h.trx_date)
from Loanhist h WHERE h.ac_no = '$id' and h.trx_type='LP'
GROUP BY principal, interest
The test data generation is for Oracle, but you should easily be able to adapt it. The actual query will work on SQL server. You'll need to use an approach like this if the account can post more than one transaction in a day. Otherwise the 'LIMIT/TOP 1' approaches in the other answers will work fine.
CREATE GLOBAL TEMPORARY TABLE balances
( ac_no CHAR(100),
principal FLOAT,
interest FLOAT,
tranDate DATE
)
ON COMMIT PRESERVE ROWS;
INSERT INTO balances VALUES (1,123.123,.456,DATE '2017-01-01');
INSERT INTO balances VALUES (1,100,.456,DATE '2017-01-02');
INSERT INTO balances VALUES (1,200,.1,DATE '2017-01-02');
INSERT INTO balances VALUES (2,200,.1,DATE '2017-01-02');
INSERT INTO balances VALUES (2,300,.1,DATE '2017-01-02');
SELECT SUM
( CASE WHEN tranDate = max_tran_date
THEN principal + interest
ELSE 0
END
) AS tranSum
FROM (SELECT sub.*,
MAX(tranDate) OVER() AS max_tran_date
FROM balances sub
) BAL;
Your question is not really clear. But if you just want to get the last transaction performed by the user, the best thing to do will be to rely on IDs instead of dates.
SELECT TOP 1 * FROM Loanhist h WHERE h.trx_type='LP' ORDER BY h.ac_no DESC
try to use LIMIT keyword.For Example, Select * from table name where condition LIMIT 1.It will return first row
Try this:
SELECT TOP 1 sum(h.principal+h.interest) as amt_paid, h.trx_date
FROM Loanhist h WHERE h.ac_no = '$id' AND h.trx_type='LP'
ORDER BY h.ac_no DESC;
Related
I have an orders grid holding 1 million records. The page has pagination, sort and search options. So If the sort order is set by customer name with a search key and the page number is 1, it is working fine.
SELECT * FROM orders WHERE customer_name like '%Henry%' ORDER BY
customer_name desc limit 10 offset 0
It becomes a problem when the User clicks on the last page.
SELECT * FROM orders WHERE customer_name like '%Henry%' ORDER BY
customer_name desc limit 10 offset 100000
The above query takes forever to load. Index is set to the order id, customer name, date of order column.
I can use this solution https://explainextended.com/2009/10/23/mysql-order-by-limit-performance-late-row-lookups/ if I don't have a non-primary key sort option, but in my case sorting is user selected. It will change from Order id, customer name, date of order etc.
Any help would be appreciated. Thanks.
Problem 1:
LIKE "%..." -- The leading wildcard requires a full scan of the data, or at least until it finds the 100000+10 rows. Even
... WHERE ... LIKE '%qzx%' ... LIMIT 10
is problematic, since there probably not 10 such names. So, a full scan of your million names.
... WHERE name LIKE 'James%' ...
will at least start in the middle of the table-- if there is an index starting with name. But still, the LIMIT and OFFSET might conspire to require reading the rest of the table.
Problem 2: (before you edited your Question!)
If you leave out the WHERE, do you really expect the user to page through a million names looking for something?
This is a UI problem.
If you have a million rows, and the output is ordered by Customer_name, that makes it easy to see the Aarons and the Zywickis, but not anyone else. How would you get to me (James)? Either you have 100K links and I am somewhere near the middle, or the poor user would have to press [Next] 'forever'.
My point is that the database is not the place to introduce efficiency.
In some other situations, it is meaningful to go to the [Next] (or [Prev]) page. In these situations, "remember where you left off", then use that to efficiently reach into the table. OFFSET is not efficient. More on Pagination
I use a special concept for this. First I have a table called pager. It contains an primary pager_id, and some values to identify a user (user_id,session_id), so that the pager data can't be stolen.
Then I have a second table called pager_filter. I consist of 3 ids:
pager_id int unsigned not NULL # id of table pager
order_id int unsigned not NULL # store the order here
reference_id int unsigned not NULL # reference into the data table
primary key(pager_id,order_id);
As first operation I select all records matching the filter rules from and insert them into pager_filter
DELETE FROM pager_filter WHERE pager_id = $PAGER_ID;
INSERT INTO pager_filter (pager_id,order_id,reference_id)
SELECT $PAGER_ID pager_id, ROW_NUMBER() order_id, data_id reference_id
FROM data_table
WHERE $CONDITIONS
ORDER BY $ORDERING
After filling the filter table you can use an inner join for pagination:
SELECT d.*
FROM pager_filter f
INNER JOIN data_table d ON d.data_id = f.reference id
WHERE f.pager_id = $PAGER_ID && f.order_id between 100000 and 100099
ORDER BY f.order_id
or
SELECT d.*
FROM pager_filter f
INNER JOIN data_table d ON d.data_id = f.reference id
WHERE f.pager_id = $PAGER_ID
ORDER BY f.order_id
LIMIT 100 OFFSET 100000
Hint: All code above is not tested pseudo code
This is my result screenshot
I need to avoid repetition of the field Total, but I need all those data in all other fields, can anyone please help to attain the result!?
Here is my SQL Query
SELECT
(SELECT SUM(credit.amount)
FROM credit,customers
WHEREcredit.date BETWEEN '2018-05-01' AND '2018-05-31'
AND credit.cus_id=customers.id) AS Total,
credit.amount, credit.date,
customers.name
FROM customers, credit
WHERE credit.date BETWEEN' 2018-05-01' AND '2018-05-31'
AND credit.cus_id=customers.id
ORDER BY credit.date
You can add a row counter and use it with a conditional function IF. If the row number is <=1 it runs the subquery otherwise it prints an empty varchar ''.
As I said in the comment, I will consider to extract the subquery and run it in a separate query, then add its result to the first row with the application.
SET #rank=0;
SELECT #rank:=#rank+1 AS rank,
IF(#rank>1,'',(SELECT SUM(credit.amount)
FROM credit,customers
WHEREcredit.date BETWEEN '2018-05-01' AND '2018-05-31'
AND credit.cus_id=customers.id)) AS Total,
credit.amount, credit.date,
customers.name
FROM customers, credit
WHERE credit.date BETWEEN' 2018-05-01' AND '2018-05-31'
AND credit.cus_id=customers.id
ORDER BY credit.date
I have MySQL table with employees attendance. first row of a day of employee treating as in time and last row of a day of employee treating as out time. I am trying to select first and last (min time and max time) from attendance table. It should give me two row sets. but my query not giving me as i expecting the result.
Table (Attendance)
My Query
select *, min(attdate) as intime, max(attdate) as outtime from attendance where empid=1
But above query not giving me as expected result. My output should be in below image. Please suggest me the query or give me hint to achieve given output.
this can be done by sub queries in where conditions.
SELECT * FROM attendance AS c WHERE empid=1 and (
attdate=( select min(attdate) from attendance where attendance.empid=c.empid )
or attdate=( select max(attdate) from attendance where attendance.empid=c.empid )
);
Unfortunately, MySQL doesn't offer window functions, so it's a bit more difficult here. You can use exists :
Select * from yourtable t
Where not exists (select 1 from yourtable s
Where t.empid = s.empid and
(s.attndate < t.attndate or s.attndate > t.attndate))
Though it seems you need to add another condition t.date = s.date unless you have only 1 day records stored there
I want per day sales item count so for that one i already created query but it takes to much around 55.585s and query is
Query :
SELECT
td.db_date,
(
select count(*) from order as order where DATE(order.created_on) = td.db_date
)as day_contribute
FROM time_dimension as td
So can any one please let me know how may i optimized this query and reduce execution time.?
You can modify your query to join like:
SELECT
td.db_date, count(order.id) as day_contribute
FROM time_dimension as td
LEFT JOIN order ON DATE(order.created_on) = td.db_date
GROUP BY td.db_date;
I do not know your primary id key for table order - so used just "order.id". Replace it with your.
Also it is very important - test if you have index on td.db_date field.
And one more important thing - better to avoid using DATE(order.created_on). Because it is mean that DATE() method will be called each time when DB will compare dates. If it is possible - convert order.created_on to same format as td.db_date. Or join by other fields. That will add speed too.
First you should make sure you have index on created_on column in order table.
However if you have many records in time_dimension and many records in order table it might be hard to optimize the query, because for each record from time_dimension you need to search in order table.
You can also change count(*) into count(order_id) (assuming primary key in order table is order_id) or add extra column with date only in order table (created_on_date with date only and index on this column) so your query could look like this:
SELECT
td.db_date,
(
select count(order_id) from order where order.created_on_date = td.db_date
)as day_contribute
FROM time_dimension as td
However it's possible the execution time might be too high if you have many records in both tables, so it might be necessary to create one extra table where you hold number of orders for each day and update it in cron or when adding/updating/deleting records in order table
I have a table of customers with a 1 recorded against their customerid on different dates.
I would like to find the sum of the 1's recorded in descending order. I'm using MySQL and php
Thanks
My guess is that you want the sum of records marked with 1 per customer and sort that result in descending order? If so, the following should do the trick :
select cust.id, sum(cone.one) as number_ones
from customers as cust
inner join customer_ones as cone on cone.id=cust.id
group by cust.id
order by number_ones desc
This is assuming that 'one' is the column containing ones (and only contains 0 or 1 - otherwise you will have to add WHERE cone.one = 1), customers is your customer table and customer_ones is the table containing your customer data.
As i get you right, this is simple sql request what u need:
SELECT COUNT(id) as total from customers
Just make in php:
$sql="SELECT COUNT(id) from customers";
$query=mysql_query($sql) or die(mysql_error());
$res=mysql_fetch_assoc($query);
$summ=$res['total']; //<- Your summ (i.e. quantity of rows in table)
Btw, you can use mysql_num_rows instead.
Or explain please more accurately what output you need. To make sorting by date or any other dependency you will need to make other request using WHERE clause and date comparison.