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@UniqueConstraint and @Column(unique = true) in hibernate annotation
What is difference between @UniqueConstraint and @Column(unique = true) ?
4 Answers
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What's the difference between the atomic and nonatomic attributes?
...e dependent properties are in play.
Consider:
@property(atomic, copy) NSString *firstName;
@property(atomic, copy) NSString *lastName;
@property(readonly, atomic, copy) NSString *fullName;
In this case, thread A could be renaming the object by calling setFirstName: and then calling setLastNam...
ERROR: permission denied for sequence cities_id_seq using Postgres
I'm new at postgres (and at database info systems all in all). I ran following sql script on my database:
4 Answers
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JPA EntityManager: Why use persist() over merge()?
EntityManager.merge() can insert new objects and update existing ones.
15 Answers
15
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Get boolean from database using Android and SQLite
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The decent way to do this would be to use
Boolean.parseBoolean(cursor.getString(booleanColumnIndex));`
though you are now limited to storing the strings "true" and "false" rather than 0 or 1.
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Cast from VARCHAR to INT - MySQL
...ution. - - - - - - - - - - - - - Long Version: From the manual: To cast a string to a number, you normally need do nothing other than use the string value in numeric context Although I'd use +0 instead of *1 since addition is faster.
– Mindwin
Oct 24 '16 at 14...
How to horizontally center a
...hat does the actual centering.
If you are targeting Internet Explorer 8 (and later), it might be better to have this instead:
#inner {
display: table;
margin: 0 auto;
}
It will make the inner element center horizontally and it works without setting a specific width.
Working example here:
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How to change the default charset of a MySQL table?
...e_prospection
CHARACTER SET utf8,
COLLATE utf8_general_ci;
To change string column charset exceute this query:
ALTER TABLE etape_prospection
CHANGE COLUMN etape_prosp_comment etape_prosp_comment TEXT CHARACTER SET utf8 COLLATE utf8_general_ci;
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Non-alphanumeric list order from os.listdir()
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You can use the builtin sorted function to sort the strings however you want. Based on what you describe,
sorted(os.listdir(whatever_directory))
Alternatively, you can use the .sort method of a list:
lst = os.listdir(whatever_directory)
lst.sort()
I think should do the...
Get bitcoin historical data [closed]
...ebClient = new System.Net.WebClient())
{
var json = WebClient.DownloadString("https://www.bitstamp.net/api/ticker/");
string value = Convert.ToString(json);
// Parse/use from here
}
From here, you can parse the JSON and store it in a database (or with MongoDB insert it directly) and...