I have tried the following syntax, which seems to work fine on SQL when I use Oracle SQL Developer. However, when I use the code in MySQL, I get ther error "Something went wrong!".
$result = mysqli_query($con, "SELECT * FROM Table1 NATURAL JOIN (SELECT ID, SUM(row2) FROM table2 GROUP BY ID) NATURAL JOIN (SELECT ID, COUNT(col1) FROM Table2 WHERE ID IS NOT NULL GROUP BY ID)")
or die("Something went wrong!");
Is there a difference in syntax in this case, or could it be anything else I'm doing wrong?
Thanks!
This is your query:
SELECT *
FROM Table1 NATURAL JOIN
(SELECT ID, SUM(row2) FROM table2 GROUP BY ID) NATURAL JOIN
(SELECT ID, COUNT(col1) FROM Table2 WHERE ID IS NOT NULL GROUP BY ID)
MySQL supports NATURAL JOIN (I don't recommend using it, but that is another matter). Unlike Oracle, you need to have table aliases on the tables, essentially names for them. You may also need column aliases. I always use them, so I don't know if they are needed.
Try this:
SELECT *
FROM Table1 t1 NATURAL JOIN
(SELECT ID, SUM(row2) as cnt_row2
FROM table2
GROUP BY ID
) t2row NATURAL JOIN
(SELECT ID, COUNT(col1) as cnt_col1
FROM Table2
WHERE ID IS NOT NULL
GROUP BY ID
) t2col1
You can actually simplify this query:
SELECT t1.*, t2.cnt_col1, t2.cnt_row2
FROM Table1 t1 INNER JOIN
(SELECT ID, COUNT(col1) as cnt_col1, SUM(row2) as cnt_row2
FROM Table2
GROUP BY ID
) t2
ON t1.id = t2.id
The filtering on ID IS NOT NULL has no effect, because a NULL value will not be included in the join.
In MySQL all the Sub queries that are used in the FROM part need an alias name. In your case its missing. And I don't use NATURAL JOIN because using other specific INNER JOIN or LEFT JOIN clarifies the condition and scenario. So may be you could rewrite your query like this to make it work:
SELECT * FROM Table1
INNER JOIN (SELECT ID, SUM(row2) FROM table2 GROUP BY ID) a
ON a.ID = Table1.ID
INNER JOIN (SELECT ID, COUNT(col1) FROM Table2 WHERE ID IS NOT NULL GROUP BY ID) b
ON b.ID = Table2.ID;
Related
I have this SQL query and I am getting an error.
SELECT
table1.id as id,
CONCAT( table2.first_name , ' ' , table2.last_name ) as name,
table2.country_code as country_code,
(select table3.id from table3 where table3.user_id = table1.id AND table3.description NOT LIKE '%SOMETEXTHERE%' LIMIT 1) as trans_id,
table4.important as important,
table1.status as status
FROM table1
LEFT JOIN table2 ON eid = table2.id
LEFT JOIN table4 ON table4.ewallet_transaction_id = trans_id
ORDER BY transaction_date desc;
The error is: Error Code: 1054. Unknown column 'trans_id' in 'on clause'
But the trans_id does exist.
Note: I also try other alias for 'trans_id' like 'transaction_id'
This might be an easy question but I just cant figure it out. Thanks for your help in advance.
Because your mix join syntax
To allow the join to be processed, group the first two tables explicitly with parentheses so that the operands for the ON clause are (t1,t2) and t3:
SELECT * FROM (t1, t2) JOIN t3 ON (t1.i1 = t3.i3);
Alternatively, avoid the use of the comma operator and use JOIN instead:
SELECT * FROM t1 JOIN t2 JOIN t3 ON (t1.i1 = t3.i3);
You have to use a JOIN FOR table3 too, this way
SELECT
table1.id as id,
CONCAT( table2.first_name , ' ' , table2.last_name ) as name,
table2.country_code as country_code,
table31.trans_id as trans_id,
table4.important as important,
table1.status as status
FROM table1
INNER JOIN (select id as trans_id, user_id from table3 where table3.description NOT LIKE '%SOMETEXTHERE%' GROUP BY 1) table31 ON table1.id=table31.user_id
LEFT JOIN table2 ON eid = table2.id
LEFT JOIN table4 ON table4.ewallet_transaction_id = table31.trans_id
ORDER BY transaction_date desc;
I am new to php & mysql and I'm trying to make a script that gets the distance walked with the player's name. I can get the player's walked distance with his id, but the value for the player_id is in a different table.
It looks like this:
Table1: player_id | foot (walked distance)
Table2: name | player_id
So I want to use the name by the player_id in my table.
Code
You require a simple join.
SELECT Table1.foot, Table2.name
FROM Table1
INNER JOIN Table2
ON Table1.player_id = Table2.player_id;
You just need to join both these table.
Just try this code:
$query = "SELECT T1.*, T2.name
FROM table1 T1
LEFT JOIN table2 T2 ON T1.player_id = T2.player_id
ORDER BY T2.name ASC";
For more details of JOIN: Link
Let me know for more help.
You can use
$query = "select t1.player_id, t2.name, t1.foot
from table1 t1
join table2 t2 on t1.player_id = t2.player_id"
If you want to order the player names in alphabetical order then you can additionally use order by clause
$query = "select t1.player_id, t2.name, t1.foot
from table1 t1
join table2 t2 on t1.player_id = t2.player_id
order by t2.name"
Use left join in mysql.
Suppose if you have two tables use this
SELECT T1.*,T2.walked distance
FROM table1 T1
LEFT JOIN table2 T2
ON T1.id=T2.player_id;
Click Here For more example
I have the following SQL query:
SELECT * FROM `table1` INNER JOIN `table2` ON table1.messageid=table2.messageid WHERE `venue_active` = 1
The above works fine but it only returns fields where both tables have a messageid field.
My problem is that I need it to return ALL fields from Table1 reguardless if it has a messageid match in table2 or not.
So, in other words I need ALL records to be returned from Table1 and all records from Table2 where there's a messageid that matches both.
How can I do this?
Use a LEFT JOIN rather
SELECT *
FROM `table1` LEFT JOIN
`table2` ON table1.messageid=table2.messageid
WHERE `venue_active` = 1
That said, it will only work if venue_active is also part of table1, and not table2.
Have a look at the different scenarios
SQL Fiddle DEMO
Use a LEFT join rather than INNER
For example:
SELECT * FROM `table1`
LEFT JOIN `table2` ON table1.messageid=table2.messageid
WHERE `venue_active` = 1
Either you need a LEFT JOIN instead, or
a FULL OUTER JOIN workaround for MySQL:
SELECT
a.*,
b.*
FROM
table1 a
LEFT JOIN
table2 b ON a.messageid = b.messageid
WHERE a.venue_active = 1
UNION
SELECT
a.*,
b.*
FROM
table1 a
RIGHT JOIN
table2 b ON a.messageid = b.messageid;
WHERE a.venue_active = 1
I have two tables Table1 and Table2 with some records
id is the common column in both tables and primarykey is set to this column in table1
There are many records in table1 and some of these records (not all) are updated into table2.
Now I want retrieve from table1 the records not updated into the table2.
For example in table1 there are records 1,2,3,4,5,6,7,8,9
And in table2 there are 3,4,7,9
Now How can I retrieve these records form table1 1,2,5,6 those not updated into table2
I wrote this query :
SELECT Table1.id, Table1.DATE, Table1.C_NAME, Table1.B_NAME
FROM [Table1] INNER JOIN Table2 ON Table1.SLIPNO <>Table2.id;
But the expected result not coming. This query lists all the records repeating each one record manytimes
Can any body give me solution to get the expected result.
select *
from table1
where table1.slip_no NOT IN (select id from table2)
Assuming name of common column is id
Or you can modify your query as
SELECT distinct (Table1.id, Table1.DATE, Table1.C_NAME, Table1.B_NAME)
FROM [Table1]
INNER JOIN Table2 ON Table1.SLIPNO <>Table2.id
A good reference on SQL joins
SELECT t1.*
FROM table1 AS t1
LEFT OUTER JOIN table2 AS t2 USING(id)
WHERE
t2.id IS NULL;
You can use the NOT IN operator on a subquery for table2.
Alternatively, use MINUS with two regular queries listing the ids in each table:
SELECT id FROM table1
MINUS
SELECT id FROM table2;
Try this
SELECT Table1.id, Table1.DATE, Table1.C_NAME, Table1.B_NAME FROM [Table1]
WHERE
NOT EXISTS (SELECT * from Table2 WHERE Table1.SLIPNO !=Table2.id );
You can use the following query
SELECT id FROM database1.table WHERE id NOT IN(SELECT id FROM database2.table)
SELECT child_table.id FROM child_table LEFT JOIN parent_table ON child_table.parent_id = parent_table.id WHERE parent_table.id IS NULL
This left join query returns all the records of the child_table when there is no match in the parent_table. When there is no match, all parent_table fields will be NULL.
inner join will not help. To get unmatched records I tried this:
SELECT
A.ID,A.DATE,A.NAME
FROM TABLE1 A
WHERE CONCAT(A.ID , A.DATE ,A.NAME)
NOT IN
(SELECT CONCAT(B.ID , B.DATE ,B.NAME) as X
from TABLE2 B) ;
I have 3 tables.
table1
id, thing_id
table_index
id
table_index_info
table_index_id, table1_id
table_index_info contains a history of table_index. This history can refer to table1, possibly many times or 0 times.
I need to run a query that returns all rows in table1 with a specific thing_id.
It also needs to count how many rows in table_index that have at least 1 table_index_info linking to table1.
Here's my query:
SELECT table1.*,
(SELECT COUNT(i.id)
FROM table_index i
WHERE EXISTS (SELECT 0
FROM table_index_info h
WHERE h.table1_id = table1.id
AND h.table_index_id = i.id)
) AS indexCount
FROM table1
WHERE table1.thing_id= $thingId
Is this the best/correct way to do this?
I would use a JOIN instead of EXISTS in this case.
SELECT table1.*,
( SELECT COUNT(i.id)
FROM table_index i
INNER JOIN table_index_info h ON h.table_index_id = i.id
WHERE h.table1_id = table1.id
) AS indexCount
FROM table1
WHERE table1.thing_id = $thingId