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What's the difference between using INDEX vs KEY in MySQL?
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Here is a nice description about the "difference":
"MySQL requires every Key also be indexed, that's an implementation
detail specific to MySQL to improve performance."
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Get record counts for all tables in MySQL database
Is there a way to get the count of rows in all tables in a MySQL database without running a SELECT count() on each table?
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MySQL Data - Best way to implement paging?
My iPhone app connects to my PHP web service to retrieve data from a MySQL database. A request can return 500 results.
7 An...
Fastest Way to Find Distance Between Two Lat/Long Points
I currently have just under a million locations in a mysql database all with longitude and latitude information.
15 Answers...
Select last row in MySQL
How can I SELECT the last row in a MySQL table?
10 Answers
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MySQL SELECT only not null values
...WHERE YourColumn IS NOT NULL;
Just for completeness I'll mention that in MySQL you can also negate the null safe equality operator but this is not standard SQL.
SELECT *
FROM table
WHERE NOT (YourColumn <=> NULL);
Edited to reflect comments. It sounds like your table may not be in first ...
Change auto increment starting number?
In MySQL, I have a table, and I want to set the auto_increment value to 5 instead of 1 . Is this possible and what query statement does this?
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MySQL combine two columns into one column
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My guess is that you are using MySQL where the + operator does addition, along with silent conversion of the values to numbers. If a value does not start with a digit, then the converted value is 0.
So try this:
select concat(column1, column2)
Two way...
How to use GROUP BY to concatenate strings in MySQL?
... id, GROUP_CONCAT(name SEPARATOR ' ') FROM table GROUP BY id;
http://dev.mysql.com/doc/refman/5.0/en/group-by-functions.html#function_group-concat
From the link above, GROUP_CONCAT: This function returns a string result with the concatenated non-NULL values from a group. It returns NULL if there ...
What does it mean when MySQL is in the state “Sending data”?
What does it mean if the Mysql query:
2 Answers
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