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How to implement one-to-one, one-to-many and many-to-many relationships while designing tables?
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One-to-one: Use a foreign key to the referenced table:
student: student_id, first_name, last_name, address_id
address: address_id, address, city, zipcode, student_id # you can have a
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Get current AUTO_INCREMENT value for any table
How do I get the current AUTO_INCREMENT value for a table in MySQL?
8 Answers
8
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MYSQL OR vs IN performance
I am wondering if there is any difference in regards to performance between the following
14 Answers
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How did Google manage to do this? Slide ActionBar in Android application
... it's clicked, collapses the menu. So, here's some code:
First, the class for collapsing / expanding (SlideMenu.java):
package your.cool.app;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.graphics.Rect;
import android.util.Log;
import a...
MySQL Insert Where query
...1, 160, 145);
If you're trying to change the weight/desiredWeight values for an existing row with ID 1 you should be using:
UPDATE Users SET weight = 160, desiredWeight = 145 WHERE id = 1;
If you want you can also use INSERT .. ON DUPLICATE KEY syntax like so:
INSERT INTO Users (id, weight, de...
Can I use CASE statement in a JOIN condition?
... 1. Your statement attempted to return the value of an assignment or test for equality, neither of which make sense in the context of a CASE/THEN clause. (If BOOLEAN was a datatype then the test for equality would make sense.)
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LEFT JOIN only first row
I read many threads about getting only the first row of a left join, but, for some reason, this does not work for me.
6 Ans...
Get generated id after insert
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@UnknownJoe I know this is old post. But may be helpful for someone. The row id and autoincremented id will be same even if it is deleted from middle.
– Raj kannan Iyyappan
Oct 4 '18 at 21:25
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How to delete a certain row from mysql table with same column values?
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@Paul This is exactly what I about to say. But don't forget unique key doesn't necessary means primary key.
– Ryan Fung
Oct 28 '15 at 7:11
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Python assigning multiple variables to same value? list behavior
...to reassign the values list separately, I mean b[0] and c[0] equal 0 as before.
9 Answers
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