Connecting mySQL table to itself to cross check results?












0















Not sure that's the best question title, but what I have is this:



db: usernames



id, username, search_via, value_1
1, Rita, Sue, 1
2, Bob, Sue, 2
3, Bill, Sue, 3
4, Jim, Bill, 4
5, Brian, Bob, 5


I want to be able to search for the all the users with a search_via of 'Sue', so obviously I have:



SELECT * FROM usernames WHERE search_via = 'Sue':
1, Rita, Sue, 1
2, Bob, Sue, 2
3, Bill, Sue, 3


...but then I want, from those results, to also return any usernames which appear as a search_via as well, so in the case it would be 'Brian', as it is a search_via value for Bob, who appeared as a username for 'Sue':



5, Brian, Bob, 5


..so my full results should be:



1, Rita, Sue, 1
2, Bob, Sue, 2
3, Bill, Sue, 3
5, Brian, Bob, 5


...because my first search_via name was Sue, and in Sue's results, there was Bob, who was a search_via value for 'Brian'



...I've really struggled explaining this, so I have absolutely zero idea how to go about it?!?



Any ideas?










share|improve this question


















  • 1





    Do you want this search result to extend to third level and beyond as well ?

    – Madhur Bhaiya
    Nov 14 '18 at 13:32











  • Why does n't 4, Jim, Bill, 4 also appear in output ? Bill is also searchable via Sue

    – Madhur Bhaiya
    Nov 14 '18 at 13:43











  • Yes, very much so.

    – TheBounder
    Nov 14 '18 at 13:44











  • "Yes, very much so" - Is this answer to my first question ? or the second question ?

    – Madhur Bhaiya
    Nov 14 '18 at 13:44











  • You're right, 'Bill' should also appear. My mistake.

    – TheBounder
    Nov 14 '18 at 13:44
















0















Not sure that's the best question title, but what I have is this:



db: usernames



id, username, search_via, value_1
1, Rita, Sue, 1
2, Bob, Sue, 2
3, Bill, Sue, 3
4, Jim, Bill, 4
5, Brian, Bob, 5


I want to be able to search for the all the users with a search_via of 'Sue', so obviously I have:



SELECT * FROM usernames WHERE search_via = 'Sue':
1, Rita, Sue, 1
2, Bob, Sue, 2
3, Bill, Sue, 3


...but then I want, from those results, to also return any usernames which appear as a search_via as well, so in the case it would be 'Brian', as it is a search_via value for Bob, who appeared as a username for 'Sue':



5, Brian, Bob, 5


..so my full results should be:



1, Rita, Sue, 1
2, Bob, Sue, 2
3, Bill, Sue, 3
5, Brian, Bob, 5


...because my first search_via name was Sue, and in Sue's results, there was Bob, who was a search_via value for 'Brian'



...I've really struggled explaining this, so I have absolutely zero idea how to go about it?!?



Any ideas?










share|improve this question


















  • 1





    Do you want this search result to extend to third level and beyond as well ?

    – Madhur Bhaiya
    Nov 14 '18 at 13:32











  • Why does n't 4, Jim, Bill, 4 also appear in output ? Bill is also searchable via Sue

    – Madhur Bhaiya
    Nov 14 '18 at 13:43











  • Yes, very much so.

    – TheBounder
    Nov 14 '18 at 13:44











  • "Yes, very much so" - Is this answer to my first question ? or the second question ?

    – Madhur Bhaiya
    Nov 14 '18 at 13:44











  • You're right, 'Bill' should also appear. My mistake.

    – TheBounder
    Nov 14 '18 at 13:44














0












0








0








Not sure that's the best question title, but what I have is this:



db: usernames



id, username, search_via, value_1
1, Rita, Sue, 1
2, Bob, Sue, 2
3, Bill, Sue, 3
4, Jim, Bill, 4
5, Brian, Bob, 5


I want to be able to search for the all the users with a search_via of 'Sue', so obviously I have:



SELECT * FROM usernames WHERE search_via = 'Sue':
1, Rita, Sue, 1
2, Bob, Sue, 2
3, Bill, Sue, 3


...but then I want, from those results, to also return any usernames which appear as a search_via as well, so in the case it would be 'Brian', as it is a search_via value for Bob, who appeared as a username for 'Sue':



5, Brian, Bob, 5


..so my full results should be:



1, Rita, Sue, 1
2, Bob, Sue, 2
3, Bill, Sue, 3
5, Brian, Bob, 5


...because my first search_via name was Sue, and in Sue's results, there was Bob, who was a search_via value for 'Brian'



...I've really struggled explaining this, so I have absolutely zero idea how to go about it?!?



Any ideas?










share|improve this question














Not sure that's the best question title, but what I have is this:



db: usernames



id, username, search_via, value_1
1, Rita, Sue, 1
2, Bob, Sue, 2
3, Bill, Sue, 3
4, Jim, Bill, 4
5, Brian, Bob, 5


I want to be able to search for the all the users with a search_via of 'Sue', so obviously I have:



SELECT * FROM usernames WHERE search_via = 'Sue':
1, Rita, Sue, 1
2, Bob, Sue, 2
3, Bill, Sue, 3


...but then I want, from those results, to also return any usernames which appear as a search_via as well, so in the case it would be 'Brian', as it is a search_via value for Bob, who appeared as a username for 'Sue':



5, Brian, Bob, 5


..so my full results should be:



1, Rita, Sue, 1
2, Bob, Sue, 2
3, Bill, Sue, 3
5, Brian, Bob, 5


...because my first search_via name was Sue, and in Sue's results, there was Bob, who was a search_via value for 'Brian'



...I've really struggled explaining this, so I have absolutely zero idea how to go about it?!?



Any ideas?







mysql






share|improve this question













share|improve this question











share|improve this question




share|improve this question










asked Nov 14 '18 at 13:30









TheBounderTheBounder

244




244








  • 1





    Do you want this search result to extend to third level and beyond as well ?

    – Madhur Bhaiya
    Nov 14 '18 at 13:32











  • Why does n't 4, Jim, Bill, 4 also appear in output ? Bill is also searchable via Sue

    – Madhur Bhaiya
    Nov 14 '18 at 13:43











  • Yes, very much so.

    – TheBounder
    Nov 14 '18 at 13:44











  • "Yes, very much so" - Is this answer to my first question ? or the second question ?

    – Madhur Bhaiya
    Nov 14 '18 at 13:44











  • You're right, 'Bill' should also appear. My mistake.

    – TheBounder
    Nov 14 '18 at 13:44














  • 1





    Do you want this search result to extend to third level and beyond as well ?

    – Madhur Bhaiya
    Nov 14 '18 at 13:32











  • Why does n't 4, Jim, Bill, 4 also appear in output ? Bill is also searchable via Sue

    – Madhur Bhaiya
    Nov 14 '18 at 13:43











  • Yes, very much so.

    – TheBounder
    Nov 14 '18 at 13:44











  • "Yes, very much so" - Is this answer to my first question ? or the second question ?

    – Madhur Bhaiya
    Nov 14 '18 at 13:44











  • You're right, 'Bill' should also appear. My mistake.

    – TheBounder
    Nov 14 '18 at 13:44








1




1





Do you want this search result to extend to third level and beyond as well ?

– Madhur Bhaiya
Nov 14 '18 at 13:32





Do you want this search result to extend to third level and beyond as well ?

– Madhur Bhaiya
Nov 14 '18 at 13:32













Why does n't 4, Jim, Bill, 4 also appear in output ? Bill is also searchable via Sue

– Madhur Bhaiya
Nov 14 '18 at 13:43





Why does n't 4, Jim, Bill, 4 also appear in output ? Bill is also searchable via Sue

– Madhur Bhaiya
Nov 14 '18 at 13:43













Yes, very much so.

– TheBounder
Nov 14 '18 at 13:44





Yes, very much so.

– TheBounder
Nov 14 '18 at 13:44













"Yes, very much so" - Is this answer to my first question ? or the second question ?

– Madhur Bhaiya
Nov 14 '18 at 13:44





"Yes, very much so" - Is this answer to my first question ? or the second question ?

– Madhur Bhaiya
Nov 14 '18 at 13:44













You're right, 'Bill' should also appear. My mistake.

– TheBounder
Nov 14 '18 at 13:44





You're right, 'Bill' should also appear. My mistake.

– TheBounder
Nov 14 '18 at 13:44












1 Answer
1






active

oldest

votes


















1














To get results upto second level hierarchy only, we can simply use a subquery to fetch all the username values where search_via = 'Sue'. We can then use WHERE search_via IN (..) to get second level hierarchy results as well.



SELECT * 
FROM usernames
WHERE search_via = 'Sue' OR
search_via IN (
SELECT username
FROM usernames
WHERE search_via = 'Sue'
)





share|improve this answer
























  • You are picking up an extra record (see here). Not that my answer seems correct either :-(

    – Tim Biegeleisen
    Nov 14 '18 at 13:40











  • @TimBiegeleisen thanks for the fiddle. Actually OP's expected output is wrong. His sample data covers all the usernames actually. Remaining two users are at second level.

    – Madhur Bhaiya
    Nov 14 '18 at 13:42











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1 Answer
1






active

oldest

votes








1 Answer
1






active

oldest

votes









active

oldest

votes






active

oldest

votes









1














To get results upto second level hierarchy only, we can simply use a subquery to fetch all the username values where search_via = 'Sue'. We can then use WHERE search_via IN (..) to get second level hierarchy results as well.



SELECT * 
FROM usernames
WHERE search_via = 'Sue' OR
search_via IN (
SELECT username
FROM usernames
WHERE search_via = 'Sue'
)





share|improve this answer
























  • You are picking up an extra record (see here). Not that my answer seems correct either :-(

    – Tim Biegeleisen
    Nov 14 '18 at 13:40











  • @TimBiegeleisen thanks for the fiddle. Actually OP's expected output is wrong. His sample data covers all the usernames actually. Remaining two users are at second level.

    – Madhur Bhaiya
    Nov 14 '18 at 13:42
















1














To get results upto second level hierarchy only, we can simply use a subquery to fetch all the username values where search_via = 'Sue'. We can then use WHERE search_via IN (..) to get second level hierarchy results as well.



SELECT * 
FROM usernames
WHERE search_via = 'Sue' OR
search_via IN (
SELECT username
FROM usernames
WHERE search_via = 'Sue'
)





share|improve this answer
























  • You are picking up an extra record (see here). Not that my answer seems correct either :-(

    – Tim Biegeleisen
    Nov 14 '18 at 13:40











  • @TimBiegeleisen thanks for the fiddle. Actually OP's expected output is wrong. His sample data covers all the usernames actually. Remaining two users are at second level.

    – Madhur Bhaiya
    Nov 14 '18 at 13:42














1












1








1







To get results upto second level hierarchy only, we can simply use a subquery to fetch all the username values where search_via = 'Sue'. We can then use WHERE search_via IN (..) to get second level hierarchy results as well.



SELECT * 
FROM usernames
WHERE search_via = 'Sue' OR
search_via IN (
SELECT username
FROM usernames
WHERE search_via = 'Sue'
)





share|improve this answer













To get results upto second level hierarchy only, we can simply use a subquery to fetch all the username values where search_via = 'Sue'. We can then use WHERE search_via IN (..) to get second level hierarchy results as well.



SELECT * 
FROM usernames
WHERE search_via = 'Sue' OR
search_via IN (
SELECT username
FROM usernames
WHERE search_via = 'Sue'
)






share|improve this answer












share|improve this answer



share|improve this answer










answered Nov 14 '18 at 13:32









Madhur BhaiyaMadhur Bhaiya

19.5k62236




19.5k62236













  • You are picking up an extra record (see here). Not that my answer seems correct either :-(

    – Tim Biegeleisen
    Nov 14 '18 at 13:40











  • @TimBiegeleisen thanks for the fiddle. Actually OP's expected output is wrong. His sample data covers all the usernames actually. Remaining two users are at second level.

    – Madhur Bhaiya
    Nov 14 '18 at 13:42



















  • You are picking up an extra record (see here). Not that my answer seems correct either :-(

    – Tim Biegeleisen
    Nov 14 '18 at 13:40











  • @TimBiegeleisen thanks for the fiddle. Actually OP's expected output is wrong. His sample data covers all the usernames actually. Remaining two users are at second level.

    – Madhur Bhaiya
    Nov 14 '18 at 13:42

















You are picking up an extra record (see here). Not that my answer seems correct either :-(

– Tim Biegeleisen
Nov 14 '18 at 13:40





You are picking up an extra record (see here). Not that my answer seems correct either :-(

– Tim Biegeleisen
Nov 14 '18 at 13:40













@TimBiegeleisen thanks for the fiddle. Actually OP's expected output is wrong. His sample data covers all the usernames actually. Remaining two users are at second level.

– Madhur Bhaiya
Nov 14 '18 at 13:42





@TimBiegeleisen thanks for the fiddle. Actually OP's expected output is wrong. His sample data covers all the usernames actually. Remaining two users are at second level.

– Madhur Bhaiya
Nov 14 '18 at 13:42




















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