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How to have an automatic timestamp in SQLite?
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Just declare a default value for a field:
CREATE TABLE MyTable(
ID INTEGER PRIMARY KEY,
Name TEXT,
Other STUFF,
Timestamp DATETIME DEFAULT CURRENT_TIMESTAMP
);
However, if your INSERT command explicitly sets this field to NULL, it will be set to NULL.
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How to “perfectly” override a dict?
... the minimal version that shuts the ABC up.
from collections.abc import MutableMapping
class TransformedDict(MutableMapping):
"""A dictionary that applies an arbitrary key-altering
function before accessing the keys"""
def __init__(self, *args, **kwargs):
self.store = dict...
Find all storage devices attached to a Linux machine [closed]
I have a need to find all of the writable storage devices attached to a given machine, whether or not they are mounted.
7...
Pros and Cons of Interface constants [closed]
...a great solid design. But there are times when good enough really is acceptable (and it takes an experienced developer to understand the difference), and in those cases it's fine.
Again, that's just my view on it...
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Long press on UITableView
I would like to handle a long press on a UITableViewCell to print a "quick access menu".
Did someone already do this?
10...
Why isn't SQL ANSI-92 standard better adopted over ANSI-89?
...e one and the USING Clause is another. IMHO, the addition of a column to a table shouldn't break code but a NATURAL JOIN breaks in a most egregious fashion. The "best" way to break is by compilation error. For example if you SELECT * somewhere, the addition of a column could fail to compile. The nex...
Insert/Update Many to Many Entity Framework . How do I do it?
...a Student object that has a collection of Classes. Since your StudentClass table only contains the Ids and no extra information, EF does not generate an entity for the joining table. That is the correct behaviour and that's what you expect.
Now, when doing inserts or updates, try to think in terms ...
Regular expression for a string that does not start with a sequence
I'm processing a bunch of tables using this program , but I need to ignore ones that start with the label "tbd_". So far I have something like [^tbd_] but that simply not match those characters.
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What does the brk() system call do?
...does stuff (after I drew it I discovered that Linux actually puts the executable much closer to address zero than I thought it did, and the shared libraries at surprisingly high addresses). The black regions of this diagram are unmapped -- any access causes an immediate segfault -- and they are giga...
How to use NULL or empty string in SQL
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Select *
From Table
Where (col is null or col = '')
Or
Select *
From Table
Where IsNull(col, '') = ''
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