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Why is a “GRANT USAGE” created the first time I grant a user privileges?
...e MySQL server, hence USAGE. It corresponds to a row in the `mysql`.`user` table with no privileges set.
The IDENTIFIED BY clause indicates that a password is set for that user. How do we know a user is who they say they are? They identify themselves by sending the correct password for their accoun...
Detect if value is number in MySQL
...
This should work in most cases.
SELECT * FROM myTable WHERE concat('',col1 * 1) = col1
It doesn't work for non-standard numbers like
1e4
1.2e5
123. (trailing decimal)
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Can I store images in MySQL [duplicate]
...need to save as a blob, LONGBLOB datatype in mysql will work.
Ex:
CREATE TABLE 'test'.'pic' (
'idpic' INTEGER UNSIGNED NOT NULL AUTO_INCREMENT,
'caption' VARCHAR(45) NOT NULL,
'img' LONGBLOB NOT NULL,
PRIMARY KEY ('idpic')
)
As others have said, its a bad practice but it can be don...
SQL Update with row_number()
... attempt failed primarily because you named the CTE same as the underlying table and made the CTE look as if it was a recursive CTE, because it essentially referenced itself. A recursive CTE must have a specific structure which requires the use of the UNION ALL set operator.
Instead, you could just...
What is the best way to stop people hacking the PHP-based highscore table of a Flash game
...both these conditions are true, it writes the high score to the high score table and returns a signed "success" message to the client. It also removes the salt value from the pending query list.
Please keep in mind that the security of any of the above techniques is compromised if the shared secr...
Postgresql query between date ranges
...= 2
This involves calculating the conditions for every single row in the table (a scan) and not using index to find the range of rows that will match (a range-seek).
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JPA: what is the proper pattern for iterating over large result sets?
Let's say I have a table with millions of rows. Using JPA, what's the proper way to iterate over a query against that table, such that I don't have all an in-memory List with millions of objects?
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Understanding “randomness”
...et after multiplying two random variables:
BarChart[BinCounts[Table[RandomReal[{0, 1}, 50000] *
RandomReal[{0, 1}, 50000], {50000}], 0.01]]
So, both are “random”, but their distribution is very different.
Another example
While 2 * Random() is un...
How to set the UITableView Section title programmatically (iPhone/iPad)?
I've created a UITableView in Interface Builder using storyboards . The UITableView is setup with static cells and a number of different sections.
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How can I get around MySQL Errcode 13 with SELECT INTO OUTFILE?
I am trying to dump the contents of a table to a csv file using a MySQL SELECT INTO OUTFILE statement. If I do:
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