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Best way to test if a row exists in a MySQL table
I'm trying to find out if a row exists in a table. Using MySQL, is it better to do a query like this:
12 Answers
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MySQL select 10 random rows from 600K rows fast
...imple, to gaps, to non-uniform with gaps.
http://jan.kneschke.de/projects/mysql/order-by-rand/
For most general case, here is how you do it:
SELECT name
FROM random AS r1 JOIN
(SELECT CEIL(RAND() *
(SELECT MAX(id)
FROM random)) AS id)
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Is there a simple way to convert C++ enum to string?
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I love this solution. It would be clearer if SOME_UNION and MAKE_UNION were called SOME_ENUM and MAKE_ENUM, though.
– Bruno Martinez
Jan 8 '13 at 14:26
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When to use single quotes, double quotes, and backticks in MySQL
...le and column identifiers, but are only necessary when the identifier is a MySQL reserved keyword, or when the identifier contains whitespace characters or characters beyond a limited set (see below) It is often recommended to avoid using reserved keywords as column or table identifiers when possibl...
Get query from java.sql.PreparedStatement [duplicate]
...To my experience, the ones which do so are at least the PostgreSQL 8.x and MySQL 5.x JDBC drivers. For the case your JDBC driver doesn't support it, your best bet is using a statement wrapper which logs all setXxx() methods and finally populates a SQL string on toString() based on the logged informa...
Inserting a Python datetime.datetime object into MySQL
I have a date column in a MySQL table. I want to insert a datetime.datetime() object into this column. What should I be using in the execute statement?
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String concatenation in MySQL
I am using MySQL and MySQL Workbench 5.2 CE. When I try to concatenate 2 columns, last_name and first_name , it doesn't work :
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UTF-8 all the way through
...character set on all tables and text columns in your database. This makes MySQL physically store and retrieve values encoded natively in UTF-8. Note that MySQL will implicitly use utf8mb4 encoding if a utf8mb4_* collation is specified (without any explicit character set).
In older versions of MyS...
Sqlite or MySql? How to decide? [closed]
...buffer parts of your 1Tb database in your 32G of memory.
You need to use mysql or some other server-based RDBMS.
Note that MySQL is not the only choice and there are plenty of others which might be better for new applications (for example pgSQL).
Sqlite is a very, very nice piece of software, bu...
Saving timestamp in mysql table using php
I have a field in a MySQL table which has a timestamp data type. I am saving data into that table. But when I pass the timestamp ( 1299762201428 ) to the record, it automatically saves the value 0000-00-00 00:00:00 into that table.
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