I currently am using this query to select some data:
SELECT DISTINCT a.code AS code, name, max(scen.Is3D) AS Is3D FROM locations LEFT JOIN .... The scen table has columns Is3D and Date. I only want to select the max of items where the date IS NOT NULL. I tried max(scen.Is3D WHERE scen.Date IS NOT NULL), but that didn't work. I cannot change anything after the FROM in my query, so I need that filtering to be done in the MAX, if possible. I am using MySQL 5.7.
You can use:
MAX(CASE WHEN scen.date IS NOT NULL THEN scen.Is3D END) AS Is3D
The CASE expression returns NULL when none of the WHEN conditions is met, but MAX() ignores null values, so this will just return the max of the Is3D columns in the selected rows.
So if we can't change anything after the FROM, then we cannot get a perfect solution here. Since you are SELECTing out the NULL values. One thing that we can try if we can only modify the final output is this.
SELECT MAX(ISNULL(scen.Date,0))...
This will replace all the NULLs with 0, but it would help to know exactly what you are trying to do. Why are you so convinced that the query itself cannot be modified in any way?
The other solution would be to put the whole query in another wrapper.
That would look like:
SELECT *
FROM (
[your whole query here]
) AS inner
WHERE inner.Date IS NOT NULL
Related
How to select COALESCE result to format( , 0)
my query is
SELECT (COALESCE((SELECT SUM(`invoices`.`paid_amount`) FROM `invoices`
WHERE DATE(`invoices`.`date`)=CURDATE()),0) +
COALESCE((SELECT SUM(`other_incomes`.`other_income_amount`) FROM `other_incomes`
WHERE DATE(`other_incomes`.`date`)=CURDATE()),0))
AS total
FROM
....
Primarily, COALESCE doesn't change the formatting. It only returns the first non-null value passed to it.
Also, instead of trying to join or do two different queries and adding, and handling all the sums and coalesces separately (not to mention the rounding), I would probably UNION all the relevant results together, then handle the coalesce/sum/round all at the end.
Try this:
SELECT round(sum(coalesce(amt, 0)), 0) as total
FROM (
SELECT paid_amount as amt
FROM invoices i
WHERE date(i.date) = CURDATE()
union all
SELECT other_income_amount
FROM other_incomes o
WHERE date(o.date) = CURDATE()
) z
Here I COALESCE first, to make nulls be 0 instead. I wrap that in a SUM to add up the values, and finally a ROUND to get the format. It was unclear from the question is you wanted to ROUND or FLOOR. If you are looking to get it with that comma, use FORMAT. Here's the mySQL documentation for that. You didn't specify your SQL flavor.
https://dev.mysql.com/doc/refman/8.0/en/string-functions.html#function_format
Additionally, you should include your sql platform and version, the create statements for your tables, along with some insert statements that will provide sample data, along with the results you are looking for. It will help people answer your question. If you can include a fiddle, like https://dbfiddle.uk/, that would be nice.
I have an sql query that could potentially return null values, in the event of this I want the query to return '0'. Here is the query
SELECT (select count(goal) from fixtures where goal='1' and fixture='$fixture') as goalCountHome
from fixtures where fixture='$fixture'LIMIT 1
Any help much appreciated!
In MySql use IFNULL() function. For MsSql use ISNULL() function.
If you are using MySql, IFNULL(<column_name>, 0) should do.
This query:
SELECT (select count(goal) from fixtures where goal='1' and fixture='$fixture') as goalCountHome
FROM fixtures
WHERE fixture = '$fixture'
LIMIT 1
cannot return NULL values. The subquery is an aggregation query with no GROUP BY, so it always returns one row. That row will contain a result from COUNT(). COUNT() itself can never return a NULL value. If there are no rows, then the value will be zero.
The outer query might return no rows but that is different from NULL values.
Of course, this query is way overcomplicated, and should simply be:
SELECT COUNT(*) as goalCountHome
FROM fixtures
WHERE fixture = ? AND -- pass this in as a parameter
goal = 1 ; -- it looks like a number so I assume it is
Note that you should be passing parameters in using proper parameters rather than munging query strings.
if you need all the rows and not the rows where goal is not null you could use count(*)
select count(*)
from fixtures
where goal=1
and fixture='$fixture'
count(goal) return the number of rows where goal is not null
count(*) return the total number rows selected
otherwise in general when you need not null values in mysql you can ifnull(your_column, value) or coalesce(your_column, value)
based on you comment seems you need sum(goal)
select sum(ifnull(goal,0))
from fixtures
where goal=1
and fixture='$fixture'
I want to be able to do a select on all columns, displaying a 0 (for a few of them) if null, without having to write each of the columns' names in the statement.
All I could think of is something like this:
SELECT *, IFNULL(`nullable_col1`, 0) FROM `my_table`;
What's the right way to do this?
No there is no way. You have to use the IFNULL function on each column which you want to have the value for.
One thing which you can do is that, you can simply select the value for all the columns which are not NULL(but I am not sure if that is what you want)
SELECT * FROM my_table WHERE (nullable_col1 AND nullable_col2 AND nullable_col2) IS NOT NULL
So this will select only columns which are not NULL.
We are fetching list of ordered products from database including join with order table.
We want to list all orders with how many quantity of products order in each order on the basis of passed product ids. We also want to display customer name which was placed the order. So, as per our knowledge we have created an query to get items as:
SELECT
`main_table`.*,
`order`.*,
SUM(main_table.qty_ordered - main_table.qty_canceled) AS `custom_qty`,
SUM(main_table.row_total) AS `custom_row_total`,
SUM(main_table.tax_amount) AS `tax_amount`,
SUM(main_table.hidden_tax_amount) AS `hidden_tax_amount`,
SUM(main_table.discount_amount) AS `discount_amount`,
CONCAT(order.customer_firstname, ' ' ,order.customer_middlename, ' ', order.customer_lastname) AS full_name
FROM `sales_flat_order_item` AS `main_table`
INNER JOIN `sales_flat_order` AS `order` ON main_table.order_id=order.entity_id
WHERE (((((main_table.product_id = '902') OR (main_table.product_id = '903') OR (main_table.product_id = '904'))))) AND (main_table.store_id = '1') AND (CONCAT(order.customer_firstname, order.customer_middlename, order.customer_lastname) like '%rag%')
GROUP BY `main_table`.`sku`
All the aggregate functions used in above query working fine except concat(). Every time we will get the value of full_name column as NULL even we have name the corresponding concatenated columns.
Please any one helps me to figure out why this is not working. Are we doing something wrong in the above query?
Thanks in advance.
As CONCAT() returns NULL if any argument is NULL I'm guessing maybe one of the three arguments is NULL?
Try using the CONCAT_WS() function instead (as you use separators anyway) which skips null values.
CONCAT_WS(' ', order.customer_firstname, order.customer_middlename, order.customer_lastname) AS full_name
See the documentation for more information.
On a side note: you might want to look into how you can use table aliases to shorten the query text and make it more readable.
Are you sure EVERY column has an value? (Middlename?)
The MYSQL manual says:
SELECT CONCAT('My', NULL, 'QL')
-> NULL
Is there any select query that set value as 0 even if it is empty or no record stored in database?
Because I am trying to subtract values from two different tables. But the problem is that I cant subtract the the tables if one of them is no data stored.
Here is my code. This code can subtract if both tables have value.
SELECT category,(SELECT SUM(s.total)-SUM(r.total)
FROM rsales AS s WHERE r.pcode=s.pcode
) as total,
r.pcode
FROM rreturn AS r
GROUP BY r.pcode;
Use IFNULL or COALESCE:
SELECT IFNULL(SUM(s.total), 0)
SELECT COALESCE(SUM(s.total), 0)
If expr1 is not NULL, IFNULL() returns expr1; otherwise it returns expr2.
IFNULL() returns a numeric or string value, depending on the context in which it is used.
something like this should work
SUM(IF(s.total, s.total, 0))
OR
SUM(IFNULL(s.total), 0))
The syntax you're using is both confusing and error prone. I would go for something simpler like this:
SELECT category, SUM(s.total) - SUM(r.total) total
FROM rsales s
LEFT JOIN rreturn r USING (pcode)
GROUP BY s.pcode;
This assumes rreturn may not have records for each pcode.