Reason: liquibase.exception.DatabaseException with DELETE statement in MySQL 5.7 - mysql

I have been trying to execute the below query in Mysql 5.7.
DELETE FROM tablename1 T1
WHERE EXISTS (
SELECT *
FROM tablename1 T2
WHERE T2.code = T1.code
AND T2.dname = T2.dname
AND T2.created_date > T1.created_date
);
But it throws me an error :
Reason: liquibase.exception.DatabaseException: You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near 'T1
This query works fine in Oracle but for some reason 'alias' doesnt work in MySQL 5.7
Is there anyway I can fix this issue within this Mysql 5.7 version.
Thanks in advance.

I am fairly sure the issue is not the alias, but subquerying the table you are deleting from, try this instead.
DELETE T1
FROM tablename1 AS T1
INNER JOIN tablename1 AS T2
ON T2.code = T1.code
AND T2.dname = T2.dname
AND T2.created_date > T1.created_date
;
I'm not positive it will work either, since it is still referencing the delete subject twice; but it is worth trying.

Related

Mysql LIKE %...% together with table

I have 2 tables with phone numbers.
In Table A I have to delete all phone numbers thats not in Table B.
In Table B the phonenumbers are with conterycode, but in Table A they are without conterycode.
I therefor try to use a command similar to LIKE %Phonenumber%
I have tried this code, but that is giving me a syntax error
DELETE FROM temp_table
WHERE NOT EXISTS (
SELECT *
FROM TableB
WHERE WorkTelephoneNumber LIKE temp_table.%PhoneNumber%
);
#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near '%PhoneNumber%
)' at line 5
You can try below -
DELETE FROM temp_table
WHERE NOT EXISTS (
SELECT *
FROM TableB
WHERE WorkTelephoneNumber LIKE concat('%',temp_table.PhoneNumber,'%')
);
A subquery will be very slow. you can use join instead
Delete t1 from temp_table t1
join TableB on tableB.WorkTelephoneNumber like concat('%',t1.PhoneNumber,'%')

Query to update and delete records in two different tables

I want to write a query that deletes a record from a table and updates a record in anther one. This is my query:
DELETE FROM borrowed_books a WHERE a.id = '$id'
AND
UPDATE books b SET b.nr_copies=b.nr_copies+1 where
b.id_book=a.id_book
The error in console says:
You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version
I am using mySQL and XAMPP.
You can't do two action in a query
you must use two query
DELETE FROM borrowed_books a WHERE a.id = '$id'
;
UPDATE books b
INNER JOIN borrowed_books a
SET b.nr_copies=b.nr_copies+1
where b.id_book=a.id_book
and a.id = '$id'
;
using update with join
eventually you can check for your mysql driver for multiple query in a command

Can aliases be used in a SQL delete query?

I have the following SQL query:
DELETE FROM table_b b WHERE NOT EXISTS (SELECT * FROM table_a a WHERE a.some_id = b.some_id)
and am getting the following error:
[Err] 1064 - You have an error in your SQL syntax; check the manual
that corresponds to your MySQL server version for the right syntax to
use near 'b WHERE NOT EXISTS(SELECT * FROM table_a a WHERE a.some_id =
b.some_id)' at line 1
this seems to suggest that aliases cannot be used with SQL delete statements (?)
Yes you can use alias in DELETE query. Just you have use that alias after DELETE keyword than it will work. It specifies that from which table you have delete the records.
Try this:
DELETE b
FROM table_b b
WHERE NOT EXISTS (SELECT * FROM table_a a WHERE a.some_id = b.some_id)
If I'm understanding your query correctly and your wanting to delete all records that are not in table a from table b. A cleaner way to write it might be
DELETE FROM table_b WHERE id NOT IN (SELECT id FROM table_a)

How to crosscheck two tables and insert relevant data into a new table in MYSQL?

I'm trying to cross-check a row that exists in two tables using a MySQL query in phpmyadmin and then, if a userID is found in both tables, insert their userID and user name into another table. Here's my code:
INSERT INTO userswithoutmeetings
SELECT user.userID
IF('user.userID'='meeting.userID');
I keep getting plagued by this error:
#1064 - You have an error in your SQL syntax; check the manual that corresponds
to your MySQL server version for the right syntax to use near
'IF('user.userID'='meeting.userID')' at line 3
Other statements I've tried have worked but not deposited the values in the table.
Something like
INSERT INTO userswithoutmeetings(userId,userName)
SELECT DISTINCT a.userId, a.userName
FROM table1 a
INNER JOIN table2 b ON (a.userId = b.userId)

Can SELECT but can't DELETE

I'm having difficulty deleting the desired rows from my table in MySQL. I'm using a rather complex subquery to select the rows, but for some reason I'm unable to delete them using a similar syntax.
delete * from table1 as t1
where t1.col1 in
(select y.col1
from table2 x
join
(select col1, col2
from table2
where col2 like "%- 2%") y
on x.col2 = replace(y.col2, "- 2", ""));
Again, I can select the exact rows I wanted deleted, but when I change the query to delete I get the following error:
ERROR 1064 (42000): You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near...
Any help is greatly appreciated.
Remove the * after DELETE. You don't usually delete individual columns, you delete entire rows.
yep, you should use
delete from table1
or if there are more than one table in the query, you need to enter the name of the table you want to delete from.
delete table1 from table1 inner join table2 on table1.id = table2.t1ID
Drop the *. A DELETE is an all or nothing kind of action.
Try DELETE FROM instead of DELETE * FROM which is not valid.