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What does it mean by select 1 from table?
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SELECT 1 FROM TABLE_NAME means, "Return 1 from the table". It is pretty unremarkable on its own, so normally it will be used with WHERE and often EXISTS (as @gbn notes, this is not necessarily best practice, it is, however, common enough t...
Dump a mysql database to a plaintext (CSV) backup from the command line
...only convenient for mysql to read. CSV seems more universal (one file per table is fine). But if there are advantages to mysqldump, I'm all ears. Also, I'd like something I can run from the command line (linux). If that's a mysql script, pointers to how to make such a thing would be helpful.
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What's the difference between belongs_to and has_one?
...oreign key is. We can say that a User "has" a Profile because the profiles table has a user_id column. If there was a column called profile_id on the users table, however, we would say that a Profile has a User, and the belongs_to/has_one locations would be swapped.
here is a more detailed explanat...
How to get script of SQL Server data? [duplicate]
...analogous to the MySQL dump from SQL Server. I need to be able to pick the tables and export the schema and the data (or I can export the schema via SQL Server Management Studio and export the data separately somehow).
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CSS two divs next to each other
...etting to see it be upvoted so much. This creates a layout that is very unstable. I would advise putting the two divs in a container, and using the display: inline-block property in order to have the divs align, as some of the other answers have suggested. I am not criticizing anyone, as we're all h...
SQL Inner-join with 3 tables?
I'm trying to join 3 tables in a view; here is the situation:
12 Answers
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First-time database design: am I overengineering? [closed]
...ds. Unless you are talking about well over a million records in your main tables you seem to be on track to having a sufficiently mainstream design that performance will not be an issue on reasonable hardware.
That said, and this relates to your question 3, with the start you have you probably s...
Is there a way to get rid of accents and convert a whole string to regular letters?
...(string, Normalizer.Form.NFD);
// or Normalizer.Form.NFKD for a more "compatable" deconstruction
This will separate all of the accent marks from the characters. Then, you just need to compare each character against being a letter and throw out the ones that aren't.
string = string.replaceAll("[...
What's the best practice for primary keys in tables?
When designing tables, I've developed a habit of having one column that is unique and that I make the primary key. This is achieved in three ways depending on requirements:
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How to select the last record of a table in SQL?
This is a sample code to select all records from a table. Can someone show me how to select the last record of that table?
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