I am trying to delete rows from a table that spit out from a join:
DELETE FROM t1 WHERE company_name IN
(SELECT company_name FROM t1
LEFT OUTER JOIN t2
ON t2.company_name = t1.company_name
WHERE t2.name IS null)
Column 'company_name' in field list is ambiguous
Getting this ambiguous error while trying to make this query? Any suggestions?
MySQL doesn't like it when you try to UPDATE/DELETE a table and SELECT from the same table in the same query.
You can solve this with multi-table DELETE syntax:
DELETE t1 FROM t1 LEFT OUTER JOIN t2 USING (company_name)
WHERE t2.name IS NULL;
As the error message tells the column name company_name is not unique. Depending on your needs I believe this may solve your problem assuming you're trying to delete entries in t1 which doesn't have a corresponding row in t2 or have one but with name is null:
DELETE FROM
t1
WHERE
company_name NOT IN (
SELECT
t2.company_name
FROM
t2
WHERE
t2.name IS NOT NULL
)
Try that
DELETE FROM t1 WHERE company_name IN ( select * from (SELECT t1.company_name FROM t1 LEFT OUTER JOIN t2 ON t2.company_name = t1.company_name WHERE t2.name IS null) t )
Related
I have two tables bound through an ID field:
table1: id, name, type
table2: id, id_table1, date, status
I have to collect all the records of the table1 that have a certain value of type field and that are not been referenced in table2 plus all the records of table1 referenced in table2 that have a certain status field value.
For the first part if I remember correctly I can use the LEFT JOIN command:
LEFT JOIN table1.name
LEFT JOIN table2
ON table2.id_table1 = table1.id
WHERE (table1.value = 'value1') AND (table2.id_table1 IS NULL);
but for the second part I'm getting lost...
I'm using MySQL 5.6 and I would like to define a View to handle this.
SELECT t1.*, t2.*
FROM table1 t1
LEFT JOIN table2 t2
ON table2.id_table1 = table1.id
WHERE (t1.type= 'value1' AND t2.id IS NULL)
OR (t2.status = 'certain status' )
I would think you could just change the WHERE to:
WHERE (table1.value = 'value1')
AND (table2.id_table1 IS NULL
OR
([the other table2 status criteria)
)
;
You can try this...
SELECT T1.*,T2.*
FROM Table1 T1
LEFT JOIN Table2 T2 ON T1.Id=T2.Id_Table1
WHERE T1.Value = 'value1' AND T2.id_table1 IS NULL
UNION
SELECT T1.*,T2.*
FROM Table1 T1
INNER JOIN Table2 T2 ON T1.Id=T2.Id_Table1
WHERE T2.Status= 'Status Criteria'
I have two tables. The first table contains ID, First_Name and Last_Name.
The 2nd table contains two foreign key fields containing different ID's of the first table.
I want to be able to run a SQL query that gets reults of the 2nd table which then grabs the First_Name of each member based on the two different foreign keys.
How would I go about doing this?
select t2.*, t1a.firstname, t1b.firstname
from table2 t2
left join table1 t1a on t2.fk1 = t1a.id
left join table1 t1b on t2.fk2 = t1b.id
Suppose the second table has fields as such
userid, supervisorid ( both referring to the Id column of the first table )
you may write join to get the value like this
SELECT t2.*, ID, firstname, lastname FROM table 2 t2
LEFT OUTER JOIN table 1 t1 ON
t2.userid = t1.id
OR t2.supervisorid = t1.id
I think correct sql would be below one using OR condition in outer join or using union
SELECT t1.id,t1.name from table1 t1, table2 t2 WHERE t1.id1 = t2.id1
UNION
SELECT t1.id,t1.name from table1 t1, table2 t2 WHERE t1.id1 = t2.id0
SELECT t1.id, t1.name from table2 t2 LEFT OUTER JOIN table1 t2 ON t1.id = t2.id or t1.id1 = t2.id0
Ok. I have some data in one table, that references on multiple occasions some data in another table.
Table1 - main client table
Table2 - user defined fields
Say I have a query that shows a client id from Table1 and all attached / used "used defined fields" from Table2
SELECT t1.Id, t2.udf
FROM Table1 t1
JOIN Table2 t2 ON t1.Id = t2.Index
WHERE t1.EndDate IS NULL AND
t1.Id = '1234.9876' AND
I would get the following for a result...
ID UDF
1234.9876 100
1234.9876 110
1234.9876 118
1234.9876 124
1234.9876 198
1234.9876 256
Now, say I wanted to query this same thing, and get ONLY the ID of the Client, but ONLY IF a value for t2.udf equaling '194' did not exist. So, I would simply get
ID
1234.9876
...as a result.
Make the join a LEFT join and filer where t2.Index is null
SELECT t1.Id
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.Id = t2.Index
AND t2.UDF = 194 -- has to be before where clause
WHERE t2.Index IS NULL
AND t1.EndDate IS NULL
AND t1.Id = '1234.9876' -- not sure if you want this part
Another way by using NOT EXISTS
SELECT t1.Id
FROM Table1 t1
WHERE NOT EXISTS (SELECT 1 FROM Table2 t2 WHERE t1.Id = t2.INDEX
AND t2.UDF = 194)
AND t1.EndDate IS NULL
AND t1.Id = '1234.9876'
See also JOINS
You can add AND t2.udf not in (select udf from table2 where udf <> '194').
But #SQLMenace solution is better
This should do it.
SELECT DISTINCT t1.Id
FROM Table1 t1
LEFT JOIN Table2 t2 ON t1.Id = t2.Index
WHERE t2.UDF NOT IN (194)
AND t2.Index IS NULL
Select DISTINCT gives you unique entries that satisfy the other conditions, and the first where clause
t2.UDF NOT IN (194)
Normall would return all the rows for the t1 where the t2.UDF is not 194, but it is limited by the Select Distinct to give you only distinct id's
Try the following:
SELECT t1.Id
FROM Table1 t1
JOIN Table2 t2 ON t1.Id = t2.Index
WHERE t1.EndDate IS NULL AND
t1.Id = '1234.9876' AND
t2.udf <> '194'
I'm trying to update several rows with email addresses. T1.email is to be updated with T2.email based on T1.name existing in T2.name.
Currently, the query looks like this.
UPDATE T1
SET T1.email = T2.email
FROM Table1 T1
INNER JOIN Table2 T2 ON T1.name = T2.name
WHERE T1.name = T2.name
AND (Some conditions)
LIMIT 1398
A similiar question is asked here, but a syntax error is given.
SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column?
I've also tried updating with ANY.
UPDATE Table1
SET Table1.email = ANY
(
SELECT Table2.email FROM Table2
WHERE Table1.accountid = 901234
AND Table2.pid = 123
AND Table2.email IS NOT NULL
)
WHERE Table1.name IN
(
SELECT Table2.name FROM Table2
WHERE Table1.accountid = 19574
AND Table2.pid = 123
AND Table2.email IS NOT NULL
)
LIMIT 1398
Currently, this returns an error "SQL Error (1242): Subquery returns more than 1 row".
May be the beginning of a copy and paste job!
As detailed under UPDATE Syntax, for MySQL you want:
UPDATE Table1 T1 JOIN Table2 T2 USING (name)
SET T1.email = T2.email
WHERE (Some conditions)
LIMIT 1398
I have two tables. Both contains question id field. I want to get all records from first table that are not present in second one. I don't want to use "NOT IN" constrain as second table having more than 400000 records.
Try something like
SELECt t1.*
FROM Table1 t1 LEFT JOIN
Table2 t2 ON t1.questionID = t2.questionID
WHERE t2.questionID IS NULL
Typically you would do this using a LEFT JOIN combined with a WHERE clause selecting every row where the joined table returns no results.
SELECT t1.*
FROM Table1 t1
LEFT OUTER JOIN Table2 t2 ON t2.ID = t1.ID
WHERE t2.ID IS NULL
try:
select from t1
right join t2 on t2.id = t1.id where t2.id is null