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Rails: Why does find(id) raise an exception in rails? [duplicate]
If there is no user with an id of 1 in the database, trying User.find(1) will raise an exception.
2 Answers
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unique object identifier in javascript
I need to do some experiment and I need to know some kind of unique identifier for objects in javascript, so I can see if they are the same. I don't want to use equality operators, I need something like the id() function in python.
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HTML input - name vs. id [duplicate]
When using the HTML <input> tag, what is the difference between the use of the name and id attributes especially that I found that they are sometimes named the same?
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Get the new record primary key ID from MySQL insert query?
Let's say I am doing a MySQL INSERT into one of my tables and the table has the column item_id which is set to autoincrement and primary key .
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How do I select an entire row which has the largest ID in the table?
How would I do something like this?
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How do I drop a foreign key constraint only if it exists in sql server?
I can drop a table if it exists using the following code but do not know how to do the same with a constraint:
10 Answers
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How to implement one-to-one, one-to-many and many-to-many relationships while designing tables?
Can anyone explain how to implement one-to-one, one-to-many and many-to-many relationships while designing tables with some examples?
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SQL “select where not in subquery” returns no results
Disclaimer: I have figured out the problem (I think), but I wanted to add this issue to Stack Overflow since I couldn't (easily) find it anywhere. Also, someone might have a better answer than I do.
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Get the Last Inserted Id Using Laravel Eloquent
I'm currently using the below code to insert data in a table:
32 Answers
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MySQL ON vs USING?
In a MySQL JOIN , what is the difference between ON and USING() ? As far as I can tell, USING() is just more convenient syntax, whereas ON allows a little more flexibility when the column names are not identical. However, that difference is so minor, you'd think they'd just do away with USI...