Mixing
How to join 4 tables in mysql PDO?
I have 4 tables as below:
1) courses
| ID - > Primary Key | Name
-------------------------------
| 1 | Course 1
| 2 | Course 2
| 3 | Course 3
2) countries
| IDPrimary Key | Name
-------------------------------
| 1 | Country 1
| 2 | Country 2
| 3 | Course 3
3) universities
| ID - > Primary Key | Name | country_id
---------------------------------------------------
| 1 | University 1 | 1
| 2 | University 2 | 1
| 3 | University 3 | 3
4) university_courses
| ID - > Primary Key | university_id | course_id
----------------------------------------------
| 1 | 1 | 2
| 2 | 3 | 2
| 3 | 3 | 3
Now, I need to create one REST API in core PHP for android app in that I will get two parameters country_id and course_id. Both will contain multiple values like country_id = "3,4,5" and course_id = "1,6,8".
I have to response all the related universities according to the country and course.
I have tried below query but i am not getting desired output so please help me if anyone have idea for my problem.
SELECT *
FROM universities
LEFT JOIN countries ON countries.id = universities.country_id
LEFT JOIN university_courses ON universiity_courses.university_id = universities.id
LEFT JOIN courses ON courses.id = university_courses.course_id
WHERE FIND_IN_SET(universities.country_id, ?)
AND FIND_IN_SET(university_courses.course_id, ?)
If course_id = 1,2 and country_id = 2,3, my desired output should be:
| university_id |
| 3 |
php mysql pdo
edited Jan 1 at 13:24
RiggsFolly
71.4k1866113
asked Jan 1 at 12:38
Jk7Jk7
142
|
show 2 more comments
I have 4 tables as below:
1) courses
| ID - > Primary Key | Name
-------------------------------
| 1 | Course 1
| 2 | Course 2
| 3 | Course 3
2) countries
| IDPrimary Key | Name
-------------------------------
| 1 | Country 1
| 2 | Country 2
| 3 | Course 3
3) universities
| ID - > Primary Key | Name | country_id
---------------------------------------------------
| 1 | University 1 | 1
| 2 | University 2 | 1
| 3 | University 3 | 3
4) university_courses
| ID - > Primary Key | university_id | course_id
----------------------------------------------
| 1 | 1 | 2
| 2 | 3 | 2
| 3 | 3 | 3
Now, I need to create one REST API in core PHP for android app in that I will get two parameters country_id and course_id. Both will contain multiple values like country_id = "3,4,5" and course_id = "1,6,8".
I have to response all the related universities according to the country and course.
I have tried below query but i am not getting desired output so please help me if anyone have idea for my problem.
SELECT *
FROM universities
LEFT JOIN countries ON countries.id = universities.country_id
LEFT JOIN university_courses ON universiity_courses.university_id = universities.id
LEFT JOIN courses ON courses.id = university_courses.course_id
WHERE FIND_IN_SET(universities.country_id, ?)
AND FIND_IN_SET(university_courses.course_id, ?)
If course_id = 1,2 and country_id = 2,3, my desired output should be:
| university_id |
| 3 |
php mysql pdo
edited Jan 1 at 13:24
RiggsFolly
71.4k1866113
asked Jan 1 at 12:38
Jk7Jk7
142
1
You want to use the IN() operator
– Raymond Nijland
Jan 1 at 12:42
Any way we can use, but need proper output.
– Jk7
Jan 1 at 12:44
You are using LEFT JOIN which is wrong you need to use a INNER JOIN to get the related relations. Also you JOiN to much tables then you could. You only have to need to JOIN between university_courses and the universities to get the required results
– Raymond Nijland
Jan 1 at 12:52
Okay, now above issue is partially solved.
– Jk7
Jan 1 at 13:12
But now i m getting same university twice, ifcourse_id=2,3. So in shortGroup byis not working.
– Jk7
Jan 1 at 13:15
|
show 2 more comments
I have 4 tables as below:
1) courses
| ID - > Primary Key | Name
-------------------------------
| 1 | Course 1
| 2 | Course 2
| 3 | Course 3
2) countries
| IDPrimary Key | Name
-------------------------------
| 1 | Country 1
| 2 | Country 2
| 3 | Course 3
3) universities
| ID - > Primary Key | Name | country_id
---------------------------------------------------
| 1 | University 1 | 1
| 2 | University 2 | 1
| 3 | University 3 | 3
4) university_courses
| ID - > Primary Key | university_id | course_id
----------------------------------------------
| 1 | 1 | 2
| 2 | 3 | 2
| 3 | 3 | 3
Now, I need to create one REST API in core PHP for android app in that I will get two parameters country_id and course_id. Both will contain multiple values like country_id = "3,4,5" and course_id = "1,6,8".
I have to response all the related universities according to the country and course.
I have tried below query but i am not getting desired output so please help me if anyone have idea for my problem.
SELECT *
FROM universities
LEFT JOIN countries ON countries.id = universities.country_id
LEFT JOIN university_courses ON universiity_courses.university_id = universities.id
LEFT JOIN courses ON courses.id = university_courses.course_id
WHERE FIND_IN_SET(universities.country_id, ?)
AND FIND_IN_SET(university_courses.course_id, ?)
If course_id = 1,2 and country_id = 2,3, my desired output should be:
| university_id |
| 3 |
php mysql pdo
edited Jan 1 at 13:24
RiggsFolly
71.4k1866113
asked Jan 1 at 12:38
Jk7Jk7
142
I have 4 tables as below:
1) courses
| ID - > Primary Key | Name
-------------------------------
| 1 | Course 1
| 2 | Course 2
| 3 | Course 3
2) countries
| IDPrimary Key | Name
-------------------------------
| 1 | Country 1
| 2 | Country 2
| 3 | Course 3
3) universities
| ID - > Primary Key | Name | country_id
---------------------------------------------------
| 1 | University 1 | 1
| 2 | University 2 | 1
| 3 | University 3 | 3
4) university_courses
| ID - > Primary Key | university_id | course_id
----------------------------------------------
| 1 | 1 | 2
| 2 | 3 | 2
| 3 | 3 | 3
Now, I need to create one REST API in core PHP for android app in that I will get two parameters country_id and course_id. Both will contain multiple values like country_id = "3,4,5" and course_id = "1,6,8".
I have to response all the related universities according to the country and course.
I have tried below query but i am not getting desired output so please help me if anyone have idea for my problem.
SELECT *
FROM universities
LEFT JOIN countries ON countries.id = universities.country_id
LEFT JOIN university_courses ON universiity_courses.university_id = universities.id
LEFT JOIN courses ON courses.id = university_courses.course_id
WHERE FIND_IN_SET(universities.country_id, ?)
AND FIND_IN_SET(university_courses.course_id, ?)
If course_id = 1,2 and country_id = 2,3, my desired output should be:
| university_id |
| 3 |
php mysql pdo
php mysql pdo
edited Jan 1 at 13:24
RiggsFolly
71.4k1866113
asked Jan 1 at 12:38
Jk7Jk7
142
edited Jan 1 at 13:24
RiggsFolly
71.4k1866113
asked Jan 1 at 12:38
Jk7Jk7
142
edited Jan 1 at 13:24
RiggsFolly
71.4k1866113
edited Jan 1 at 13:24
RiggsFolly
71.4k1866113
edited Jan 1 at 13:24
RiggsFolly
71.4k1866113
71.4k1866113
asked Jan 1 at 12:38
Jk7Jk7
142
asked Jan 1 at 12:38
Jk7Jk7
142
asked Jan 1 at 12:38
Jk7Jk7
142
142
1
You want to use the IN() operator
– Raymond Nijland
Jan 1 at 12:42
Any way we can use, but need proper output.
– Jk7
Jan 1 at 12:44
You are using LEFT JOIN which is wrong you need to use a INNER JOIN to get the related relations. Also you JOiN to much tables then you could. You only have to need to JOIN between university_courses and the universities to get the required results
– Raymond Nijland
Jan 1 at 12:52
Okay, now above issue is partially solved.
– Jk7
Jan 1 at 13:12
But now i m getting same university twice, ifcourse_id=2,3. So in shortGroup byis not working.
– Jk7
Jan 1 at 13:15
|
show 2 more comments
1
You want to use the IN() operator
– Raymond Nijland
Jan 1 at 12:42
Any way we can use, but need proper output.
– Jk7
Jan 1 at 12:44
You are using LEFT JOIN which is wrong you need to use a INNER JOIN to get the related relations. Also you JOiN to much tables then you could. You only have to need to JOIN between university_courses and the universities to get the required results
– Raymond Nijland
Jan 1 at 12:52
Okay, now above issue is partially solved.
– Jk7
Jan 1 at 13:12
But now i m getting same university twice, ifcourse_id=2,3. So in shortGroup byis not working.
– Jk7
Jan 1 at 13:15
1
1
You want to use the IN() operator
– Raymond Nijland
Jan 1 at 12:42
You want to use the IN() operator
– Raymond Nijland
Jan 1 at 12:42
Any way we can use, but need proper output.
– Jk7
Jan 1 at 12:44
Any way we can use, but need proper output.
– Jk7
Jan 1 at 12:44
You are using LEFT JOIN which is wrong you need to use a INNER JOIN to get the related relations. Also you JOiN to much tables then you could. You only have to need to JOIN between university_courses and the universities to get the required results
– Raymond Nijland
Jan 1 at 12:52
You are using LEFT JOIN which is wrong you need to use a INNER JOIN to get the related relations. Also you JOiN to much tables then you could. You only have to need to JOIN between university_courses and the universities to get the required results
– Raymond Nijland
Jan 1 at 12:52
Okay, now above issue is partially solved.
– Jk7
Jan 1 at 13:12
Okay, now above issue is partially solved.
– Jk7
Jan 1 at 13:12
But now i m getting same university twice, if
course_id=2,3. So in short Group by is not working.– Jk7
Jan 1 at 13:15
But now i m getting same university twice, if
course_id=2,3. So in short Group by is not working.– Jk7
Jan 1 at 13:15
|
show 2 more comments
0
active
oldest
votes
Your Answer
StackExchange.ifUsing("editor", function () {
StackExchange.using("externalEditor", function () {
StackExchange.using("snippets", function () {
StackExchange.snippets.init();
});
});
}, "code-snippets");
StackExchange.ready(function() {
var channelOptions = {
tags: "".split(" "),
id: "1"
};
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function() {
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled) {
StackExchange.using("snippets", function() {
createEditor();
});
}
else {
createEditor();
}
});
function createEditor() {
StackExchange.prepareEditor({
heartbeatType: 'answer',
autoActivateHeartbeat: false,
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader: {
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
},
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
});
}
});
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53995496%2fhow-to-join-4-tables-in-mysql-pdo%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
0
active
oldest
votes
0
active
oldest
votes
active
oldest
votes
active
oldest
votes
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function () {
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53995496%2fhow-to-join-4-tables-in-mysql-pdo%23new-answer', 'question_page');
}
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function () {
StackExchange.helpers.onClickDraftSave('#login-link');
});
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
1
You want to use the IN() operator
– Raymond Nijland
Jan 1 at 12:42
Any way we can use, but need proper output.
– Jk7
Jan 1 at 12:44
You are using LEFT JOIN which is wrong you need to use a INNER JOIN to get the related relations. Also you JOiN to much tables then you could. You only have to need to JOIN between university_courses and the universities to get the required results
– Raymond Nijland
Jan 1 at 12:52
Okay, now above issue is partially solved.
– Jk7
Jan 1 at 13:12
But now i m getting same university twice, if
course_id=2,3. So in shortGroup byis not working.– Jk7
Jan 1 at 13:15