Mysql compares two tables and only displays the difference
I would like to find the difference between the two tables because there is a column in table 2 that was related to the id column of table 1, but unfortunately the site manager was removing items from table 1 and now there are many unrelated rows in table 2, which is causes problems on the site.
For example table structures
Table 1 table 2
ID | name ID | value (this is the ID from table 1)
1 | one 1 | 1
2 | two 2 | 2
3 | three 3 | 4
6 | six 4 | 4
7 | seven 5 | 5
6 | 5
7 | 6
8 | 7
9 | 1
10 | 1
As you can see from Table 2, some of the IDs from Table 1 are on multiple rows, and I would like to get all of them that are not presented in Table 1 as a query return.
Just to clarify this is what I would like to get from the request
Result:
ID (form table 2) | value
3 | 4
4 | 4
5 | 5
6 | 5
I know that I could use for example NOT IN, but I would have to enter about 1000 IDs and table 1 contains many more items than what is related in table 2
How can I execute a query that will return the result as above?
source to share