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@UniqueConstraint and @Column(unique = true) in hibernate annotation
...hould have unique values. The same aplies for group.
On the other hand,
@Table(
name = "product_serial_group_mask",
uniqueConstraints = {@UniqueConstraint(columnNames = {"mask", "group"})}
)
Implies that the values of mask + group combined should be unique. That means you can have, for ex...
Selecting a row of pandas series/dataframe by integer index
...ing @HYRY, see the new docs in 0.11
http://pandas.pydata.org/pandas-docs/stable/indexing.html
Here we have new operators, .iloc to explicity support only integer indexing, and .loc to explicity support only label indexing
e.g. imagine this scenario
In [1]: df = pd.DataFrame(np.random.rand(5,2),i...
Fast way of counting non-zero bits in positive integer
...se that.
To answer a question in the comments, for bytes I'd use a lookup table. You can generate it at runtime:
counts = bytes(bin(x).count("1") for x in range(256)) # py2: use bytearray
Or just define it literally:
counts = (b'\x00\x01\x01\x02\x01\x02\x02\x03\x01\x02\x02\x03\x02\x03\x03\x04'...
“Auto Layout still required after executing -layoutSubviews” with UITableViewCell subclass
Using XCode 4.5 and iOS 6, I'm developing an app with a simple table view with custom cells. I've done this a hundred times in iOS 5 and below, but for some reason the new autoLayout system is giving me a lot of trouble.
...
postgresql - replace all instances of a string within text field
...on:
replace(string text, from text, to text)
for instance :
UPDATE <table> SET <field> = replace(<field>, 'cat', 'dog')
Be aware, though, that this will be a string-to-string replacement, so 'category' will become 'dogegory'. the regexp_replace function may help you define a ...
How to use transactions with dapper.net?
I would like to run multiple insert statements on multiple tables. I am using dapper.net. I don't see any way to handle transactions with dapper.net.
...
How to load a xib file in a UIView
...
make sure check mark "also create XIB file"
I would like to perform with tableview so I choosed subclass UITableViewCell
you can choose as your requerment
XIB file desing as your wish (RestaurantTableViewCell.xib)
we need to grab the row height to set table each row hegiht
Now! need ...
SQLite DateTime comparison
...
I had the same issue recently, and I solved it like this:
SELECT * FROM table WHERE
strftime('%s', date) BETWEEN strftime('%s', start_date) AND strftime('%s', end_date)
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mysql Foreign key constraint is incorrectly formed error
I have two tables, table1 is the parent table with a column ID and table2 with a column IDFromTable1 (not the actual name) when I put a FK on IDFromTable1 to ID in table1 I get the error Foreign key constraint is incorrectly formed error . I would like to delete table 2 record if tab...
How do I design a class in Python?
...s a question of "mutability". Some objects get updated, others don't. Mutable objects must own total responsibility for their mutations.
At this point, you can start to transform nouns into class definitions. Some collective nouns are lists, dictionaries, tuples, sets or namedtuples, and you do...