For question purposes I will use minimal data for my examples.
I have a table called table1 and a column named test that looks like this:
test
5012
I am able to add an extra zero behind before the result of column test using this query:
SELECT CONCAT('0',test) as x from table1
this is the result of the query:
results table: table1
x
05012
Now I have another table called table2 looking like this:
test test2
05012 1
My question is, how do I join the two tables together based on that query above and concat the table1 with column test2 from table2? Making sure the first 4 characters of both columns test from both tables match together?
This is how table 1 should look like:
Afterquery
050121
I am curious why you wouldn't simply use table2?
select concat(t2.test, t2.test2) as afterquery
from table2 t2;
table1 doesn't seem to play a role.
If you want values in table2 filtered by table1, you can use exists:
select concat(t2.test, t2.test2) as afterquery
from table2 t2
where exists (select 1
from table1 t1
where t2.test = concat('0', t1.test)
);
You can express this as a join:
select concat(t2.test, t2.test2) as afterquery
from table2 t2 join
table1 t1
on t2.test = concat('0', t1.test);
This is useful if you want columns from both tables -- but that is not necessary to answer the question. On the other hand, this runs the risk of duplication if there are multiple matches.
I think that this should be the solution. You need to use concat in the join between table1 and table2
SELECT CONCAT('0', table1.test, table2.test2) AS Afterquery
FROM table1
INNER JOIN table2
ON CONCAT('0',table1.test) = table2.test
Slightly different approach with a sub-query:
select concat(concat_test, test2) test_results
from
(select concat('0', test) concat_test from table1) table_alias
join
table2 on substring(concat_test,1,4) = substring(test,1,4);
Related
I have two table as table1 and table2 given below:
I want to have the value of only those table_name from table1 which has there id in print_table column in table 2.
I have implemented the following query but it returns only one value:
SELECT * FROM print_tabel_permission_admin WHERE id IN (select print_table from secondary)
Use FIND_IN_SET:
SELECT DISTINCT
t1.table_name
FROM table1 t1
INNER JOIN table2 t2
ON FIND_IN_SET(t1.id, t2.print_table) > 0;
Demo
You should probably move away from storing CSV data in your tables like this. Instead, break out the IDs in table2 onto separate rows. This will make your life easier.
I need to show only results which are in Table1 and Table2 but are not in Table3. Basically, it should be something like TABLE1, Table2 except INNER JOIN between (TABLE1, Table2) and TABLE3.
Should looks like this - On left side Table1 and Table2, on right side Table3
Now I have this:
SELECT mesta_email, mesta_kod
FROM Table1
UNION ALL
SELECT mesta_email, mesta_kod
FROM Table2
// And somehow except values which are in Table3
Can somebody help me please? Thanks a lot.
There are a couple different ways to do this. I believe mysql does better with the outer join/null approach:
select t.*
from (
SELECT mesta_email, mesta_kod
FROM Table1
UNION ALL
SELECT mesta_email, mesta_kod
FROM Table2
) t left join Table3 t3 on t.mesta_email = t3.mesta_email
and t.mesta_kod = t3.mesta_kod
where t3.mesta_email is null
This assume table3 shares the same structure as the other 2 tables.
I would approach the problem almost directly as you write it, using exists and not exists:
select t1.mesta_email, t2.mesta_kod
from table1 t1
where exists (select 1
from table2 t2
where t2.mesta_email = t1.mesta_email and t2.mesta_kod = t1.mesta_kod
) and
not exists (select 1
from table3 t3
where t3.mesta_email = t1.mesta_email and t3.mesta_kod = t1.mesta_kod
);
One advantage of exists/not exists over other approaches involves duplicates. If one of the tables (say table1) has not duplicates, but the others might, there is no need to remove duplicates in the resulting data set.
I have 2 tables. I want to find out whether the values present in the first table is there in another table with a different field name.
Here is how it looks,
Table1
BillNo
43529179
43256787
35425676
25467778
24354758
45754748
Table2
BNo
113104808
25426577
268579679
2542135464
252525232
235263663
I have 137 records in table1 that needs to be checked against table2.
Instead of doing it one by one using the following command,
Select * from Table2 where BNo = '43529179';
This gives the result for just the mentioned value. Is there a way to check for all the values in a single query?
Thanks!
You can use a sub-select to compare against:
Select * from Table2 where BNo IN (SELECT BillNo FROM Table1);
That will "evalaute" to something like Select * from Table2 where BNo IN (113104808, 25426577, 268579679, 2542135464, 252525232, ...);
Join the tables, and check how many matching records there are:
select
count(*) as Matches
from
Table1 as t1
inner join Table2 as t2 on t2.BNo = t1.BillNo
You can also use a left join to pick out the records in table 1 that has no matching record in table 2:
select
t1.BillNo
from
Table1 as t1
left join Table2 as t2 on t2.BNo = t1.BillNo
where
t2.BNo is null
I'm desperate with this query. I have two tables table1 and table2, tables are identical but they have different data. I'm trying to remove duplicities by columns code and manufacturer. To do that I need in final result ID from table1 ID from table2 and also columns code and manufacturer
SELECT * FROM (
SELECT id,code,manufacturer FROM table1 WHERE manufacturer = 1
UNION SELECT id,code,manufacturer FROM table2 WHERE manufacturer = 1
) AS t GROUP BY code HAVING COUNT(*) > 1
But in result i got only values from table1. It's OK but I just need to get there id from table2 too. Please can anyone give me some tips how to do this ?
You have two basic problems:
Problem 1:
You are using UNION when you should be using UNION ALL, because UNION removes duplicates!
Problem 2:
This isn't the right way to go about the problem. You should be using a simple join, not a union.
Try this:
SELECT
t1.id as table1_id,
t2.id as table2_id,
t1.code,
t1.manufacturer
FROM table1 t1
JOIN table2 t2
ON t2.code = t1.code
AND t2.manufacturer = t1.manufacturer
WHERE manufacturer = 1 -- this WHERE clause is optional
Your use of the WHERE clause is a little odd - consider removing it to get all duplicates from all manufacturers.
I don't know why I am confused with this query.
I have two table: Table A with 900 records and Table B with 800 records. Both table need to contain the same data but there is some mismatch.
I need to write a mysql query to insert missing 100 records from Table A to Table B.
In the end, both Table A and Table B should be identical.
I do not want to truncate all the entries first and then do a insert from another table. So please any help is appreciated.
Thank you.
It is also possible to use LEFT OUTER JOIN for that. This will avoid subquery overhead (when system might execute subquery one time for each record of outer query) like in John Woo's answer, and will avoid doing unnecessary work overwriting already existing 800 records like in user2340435's one:
INSERT INTO b
SELECT a.* FROM a
LEFT OUTER JOIN b ON b.id = a.id
WHERE b.id IS NULL;
This will first select all rows from A and B tables including all columns from both tables, but for rows which exist in A and don't exist in B all columns for B table will be NULL.
Then it filter only such latter rows (WHERE b.id IS NULL),
and at last it inserts all these rows into B table.
I think you can use IN for this. (this is a simpliplification of your query)
INSERT INTO table2 (id, name)
SELECT id, name
FROM table1
WHERE (id,name) NOT IN
(SELECT id, name
FROM table2);
SQLFiddle Demo
AS you can see on the demonstration, table2 has only 1 records but after executing the query, 2 records were inserted on table2.
If it's mysql and the tables are identical, then this should work:
REPLACE INTO table1 SELECT * FROM table2;
This will insert the missing records into Table1
INSERT INTO Table2
(Col1, Col2....)
(
SELECT Col1, Col2,... FROM Table1
EXCEPT
SELECT Col1, Col2,... FROM Table2
)
You can then run an update query to match the records that differ.
UPDATE Table2
SET
Col1= T1.Col1,
Col2= T1.Col2,
FROM
Table T1
INNER JOIN
Table2 T2
ON
T1.Col1 = T2.Col1
Code also works when a group by and having clauses are used. Tested SQL 2012 (11.0.5058) Tab1 is source with new records, Tab 2 is the destination to be updated. Tab 2 also has an Identity column. (Yes folks, real world is not as neat and clean as the lab assignments)
INSERT INTO Tab2
SELECT a.T1,a.T2,a.T3,a.T4,a.Val1,a.Val2,a.Val3,a.Val4,-9,-9,-9,-9,MIN(hits) MinHit,MAX(hits) MaxHit,SUM(count) SumCnt, count(distinct(week)) WkCnt
FROM Tab1 a
LEFT OUTER JOIN Tab2 b ON b.t1 = a.t1 and b.t2 = a.t2 and b.t3 = a.t3 and b.t4 = a.t4 and b.val1 = a.val1 and b.val2 = a.val2 and b.val3 = a.val3 and b.val4 = a.val4
WHERE b.t1 IS NULL or b.Val1 is NULL
group by a.T1,a.T2,a.T3,a.T4,a.Val1,a.Val2,a.Val3,a.Val4 having MAX(returns)<4 and COUNT(distinct(week))>2 ;