mysql not equal is not working - mysql

I've a huge problem, I don't what is going on. This is my
table1
+-----+-----------------------+--------------+
| id | invoice_number | invoice_date |
+-----+-----------------------+--------------+
| 12 | 12536801244 | 2009-09-23 |
| 38 | 12585302890 | 2009-11-18 |
| 37 | 12584309829 | 2009-11-16 |
| 123 | 12627605146 | 2010-01-06 |
| 191 | 12663105176 | 2010-02-16 |
+-----+-----------------------+--------------+
and this is my second
table2
+-----+-----------------------+--------------+
| id | invoice_number | invoice_date |
+-----+-----------------------+--------------+
| 12 | 1t657801244 | 2009-09-23 |
| 20 | 12585302890 | 2009-11-18 |
| 37 | 1ss58430982 | 2009-11-16 |
| 103 | 12627605146 | 2010-01-06 |
| 121 | 12346310517 | 2010-02-16 |
+-----+-----------------------+--------------+
What I want is, I have get all invoice_numbers that are not in table2
This is my SQL query.
select t2.invoice_number FROM table1 t1
JOIN table2 t2 ON t2.invoice_number != t1.inovice_number;
But I get different result. Any body what is wrong with SQL code?

Performance wise you can use Left Join or Not EXIST
Try with Left Join
Select t2.invoice_number
FROM table1 t1
LEFT JOIN table2 t2 ON
t2.invoice_number = t1.inovice_number AND
t2.invoice_number IS NULL;
Try With Not Exist
Select t2.invoice_number
FROM table1 t1 Where Not Exist
(
SELECT NULL
FROM table2 t2
WHERE t2.invoice_number = t1.inovice_number
)
Try with Not IN
Select t2.invoice_number
FROM table1 t1
Where t1.inovice_number NOT IN
(
SELECT t2.inovice_number
FROM table2 t2
)

Why don't you simply try:
Select * from Table1
Where Table1.invoice_number NOT IN (select invoice_number from Table2)

You can use LEFT JOIN.
SELECT t1.invoice_number
FROM table1 t1
LEFT JOIN table2 t2 ON t2.invoice_number = t1.inovice_number
WHERE t2.invoice_number IS NULL

Why not use where not exists?
SELECT *
FROM table1 t1
WHERE NOT EXISTS (SELECT * FROM table2 t2 WHERE t1.invoice_number = t2.invoice_number)

That's not the correct way to query what you are looking for.
You probably need something like this:
select invoice_number from table2
where invoice_number not in (select invoice_number from table1)

select * from table1 where invoice_number NOT EXISTS (select invoice_number FROM table2 WHERE table1.invoice_number = table2.invoice_number);

select t2.id FROM table1 as t1
INNER JOIN table2 as t2 ON t2.id != t1.id;

Related

how to substract between two tables by comparing them( according to a condition ) in sql?

I have two tables like this
table1
------------------------------------
date | name | charge | coupon|
------------------------------------
10/01 | Alex | 500 | 100 |
11/01 | Max | 1000 | 200 |
13/01 | | | |
table2
------------------------------------
date | name | error | refund |
------------------------------------
10/01 | Alex | crash | |
| | | |
I want to calculate refund to table2 from table1, if theres a error in table2. Consider date and name are unique.
I tried somthing like this, but it's not correct at all. I am a beginner to SQL
SELECT date, name, charge - coupon as Refund IF( error=True FROM table2 )
FROM table1
please help how to solve this ...
Hmmm . . . I think you want a join:
select t2.*, (t1.charge - t1.coupon) as refund
from table2 t2 join
table1 t1
on t1.name = t2.name and t1.date = t2.date
where t2.error is not null;
If you want all rows, with the refund conditionally on them:
select t2.*,
(case when t2.error is not null then t1.charge - t1.coupon end) as refund
from table2 t2 join
table1 t1
on t1.name = t2.name and t1.date = t2.date;

Need help on query on same table in MySQL

I have a table with some data, and I need to make a query using that table.
I have:
+----+-----------------+--------+--------+
| Id | Name | Parent | Mark |
+----+-----------------+--------+--------+
| 1 | Name 1 | 0 | 0 |
| 2 | Name 2 | 1 | 20 |
| 3 | Name 3 | 2 | 45 |
| 4 | Name 4 | 0 | 50 |
+----+-----------------+--------+--------+
and I need:
+----+-----------------+--------+--------+
| Id | Name | Parent | Mark |
+----+-----------------+--------+--------+
| 2 | Name 2 | Name 1 | 20 |
| 3 | Name 3 | Name 2 | 45 |
+----+-----------------+--------+--------+
How can I run the query in MySQL?
You can get your result by running this query.
Select tablename.*
from tablename t1
inner join tablename t2 on t2.Id = t1.Parent ;
you can do the inner join in the same table and check if the user have parent or not
try something like
select * from marksTbl m inner join marksTbl p on m.Id = p.Parent
You can use the following using a INNER JOIN. Using this solution also exclude all rows without a matching parent.
SELECT t1.Id, t1.Name, t2.Name AS Parent, t1.Mark
FROM table_name t1 INNER JOIN table_name t2 ON t1.Parent = t2.Id
ORDER BY t1.Id ASC
In case you want to see all rows (also the rows without (matching) parents) you can use the following with LEFT JOIN:
SELECT t1.Id, t1.Name, t2.Name AS Parent, t1.Mark
FROM table_name t1 LEFT JOIN table_name t2 ON t1.Parent = t2.Id
ORDER BY t1.Id ASC
You can also use a sub-select instead of a join:
SELECT Id, Name, (SELECT Name FROM table_name t2 WHERE t2.Id = t1.Parent) AS Parent, Mark
FROM table_name t1
WHERE t1.Parent > 0
ORDER BY t1.Id ASC
demo on dbfiddle.uk

SQL to group a similar table by name

I have two similar tables
Table 1
| id | name | amount|
| 2 | Mike | 1000 |
| 3 | Dave | 2500 |
Table 2
| id | name | amount|
| 2 | Mike | 1200 |
| 4 | James| 2500 |
I want to query the tables to get a result like this:
| id | name | amount_table1| amount_table2|
| 2 | Mike | 1000 | 1200 |
| 3 | Dave | 2500 | |
| 4 | james| | 2500 |
UNION ALL the tables. Do GROUP BY to get one row per id/name combo.
select id, name, sum(amount1), sum(amount2)
from
(
select id, name, amount as amount1, null as amount2 from table1
union all
select id, name, null, amount from table2
) dt
group by id, name
You need to do union with left and right join
select a.id , a.name , a.amount amount_table1,b.amount amount_table2 from table1 a left join table2 b on (a.id=b.id)
union
select b.id , b.name ,a.amount,b.amount from table1 a right join table2 b on (a.id=b.id)
MySql doesn't support FULL OUTER JOIN.
But it supports LEFT & RIGHT joins and UNION.
select
t1.id, t1.name, t1.amount as amount_table1, t2.amount as amount_table2
from Table1 t1
left join Table2 t2 on t1.id = t2.id
union all
select t2.id, t2.name, t1.amount, t2.amount
from Table2 t2
left join Table1 t1 on t2.id = t1.id
where t1.id is null
The first select will get those only in Table1 and those in both.
The second select will get those only in Table2.
And the UNION glues those resultsets together.
If this were for a database that supports FULL JOIN then it would be simplified to:
select
coalesce(t1.id, t2.id) as id,
coalesce(t1.name, t2.name) as name,
t1.amount as amount_table1,
t2.amount as amount_table2
from Table1 t1
full join Table2 t2 on t1.id = t2.id

SQL select MAX from other table

I have two tables.
table1:
| ID | NAME |
|----|------|
| 1 | aaa |
| 2 | aaa |
| 3 | aaa |
| 4 | bbb |
| 5 | bbb |
table2:
| ID | DATE |
|----|----------|
| 1 | 12/07/10 |
| 2 | 12/07/13 |
| 3 | 12/07/16 |
| 4 | 12/07/08 |
| 5 | 12/07/20 |
Help me pls, I don't know how to SELECT MAX ID in table1 by date in table2.
For example result should be:
for "aaa": ID 3 from table2
for "bbb": ID 5 from table2
I'm trying something like that:
DATE = (SELECT MAX(DATE) FROM table2 t2, table1 t1 WHERE t1.NAME = "aaa")
But it's not working... Have you got some idea?
You need to add an additional condition (t1.id = t2.id) for the join:
SELECT MAX(DATE)
FROM table2 t2, table1 t1
WHERE t1.NAME = "aaa"
AND t1.id = t2.id
But please - don't join with comma - use explicit JOIN syntax instead:
SELECT MAX(DATE)
FROM table2 t2
JOIN table1 t1
ON t1.id = t2.id
WHERE t1.NAME = "aaa"
You can also get all max dates for all names at once using GROUP BY name:
SELECT t1.NAME, MAX(t2.DATE)
FROM table2 t2
JOIN table1 t1
ON t1.id = t2.id
GROUP BY t1.NAME
I have tried to take the MAX Date using this query.
Note: In the table the date format should be (Y-m-d) and the field should be set to date in order to manipulate the operations
Table - 1(Name: test1)
Table - 2(Name: test2)
QUERY TO GET MAX FROM OTHER TABLE
SELECT MAX(dates) FROM test2 JOIN test1 WHERE test1.name='aaa'
OUTPUT
Hope so this query will solve your problem.
select ID from Table1 where date= (select max(date) from T2 where name= 'aaa'
i didn't fully got you. But I think this is how you want it.... If you had these two table as one table then it would work as charm.
Or THIS ,with Two Table like you asked for
SELECT T1.Id FROM T1 INNER JOIN T2
ON T1.Id = T2.Id
where T2.date = (select max(T2.date) from T1 where T1.name= 'aaa')

Merge two tables, inheriting values from one to another

I have two tables that I would like to display as a single result, using UNION or other technique.
The ID field relates both tables.
The second table has one field missing, so that missing value should be assumed from the first table.
The sample code below works, but is very slow for large datasets.
Is there any solution more efficient?
T1: T2:
+----+-------+--------+ +----+------+
| id | name | town | | id | name |
+----+-------+--------+ +----+------+
| 1 | Alice | London | | 1 | Bob |
| 2 | Alan | Zurich | +----+------+
+----+-------+--------+
Desired result:
+----+-------+--------+
| id | name | town |
+----+-------+--------+
| 1 | Alice | London |
| 2 | Alan | Zurich |
| 1 | Bob | London |
+----+-------+--------+
Sample code:
with T1 as
(
select * from
(
values
(1,'Alice','London') ,
(2,'Alan','Zurich')
) as t (id,name,town)
), T2 as
(
select * from
(
values
(1,'Bob')
) as t (id,name)
), T2WithTown as
(
select t2.id,t2.name,t1.town from T2
inner join T1 on t2.id=t1.id
)
select id,name,town from T1
union
select id,name,town from T2WithTown
The sample data shows both tables have distinct values. So I will prefer UNION ALL
Select ID, Name, Town From T1
UNION ALL
select T2.ID, T2.Name, T1.Town
from T1
INNER JOIN T2 on T2.id = T1.id
Just like this:
with T1 as
(
select * from
(
values
(1,'Alice','London') ,
(2,'Alan','Zurich')
) as t (id,name,town)
), T2 as
(
select * from
(
values
(1,'Bob')
) as t (id,name)
), T2WithTown as
(
select t2.id,t2.name,t1.town from T2
inner join T1 on t2.id=t1.id
)
select id,name,town from T1
union
select T2.id, T2.name, T1.town
from T1
inner join T2 on T2.id = T1.id
select id,name, town from t1
union
select id,name, (select top 1 town from t1 where t1.id=t2.id) from t2