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Why do you create a View in a database?
...e a View in their database? Why not just run a normal stored procedure or select?
25 Answers
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XPath: How to select elements based on their value?
...st thing is when using [], there are only two types of data:
[number] to select a node from node-set
[bool] to filter a node-set from node-set
In this case, the value is evaluated to boolean by function boolean(), and there is a rule:
Filters are always evaluated with respect to a context.
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Select Pandas rows based on list index
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For large datasets, it is memory efficient to read only selected rows via the skiprows parameter.
Example
pred = lambda x: x not in [1, 3]
pd.read_csv("data.csv", skiprows=pred, index_col=0, names=...)
This will now return a DataFrame from a file that skips all rows except 1 and ...
iOS 7 - Failing to instantiate default view controller
...ard, click anywhere in the white area and press command-a, then command-c (select all and copy)
Open your new storyboard and press command-v to paste the same exact setup
Go to your project settings, change your "Main Interface" to the new Main_iPhoneV2 (If it's your iPad and you're writing a univer...
Nexus 7 not visible over USB via “adb devices” from Windows 7 x64
...he Nexus, or undoubtedly any other device. Not exactly obvious, but if you select the second option "Camera (PTP)" the device is available for debugging (the lesson is ignore the camera, and focus on the protocol PTP).
This configuration is persistent, and I'm guessing that with a brand new device...
What is SELF JOIN and when would you use it? [duplicate]
...et information for both people in one row, you could self join like this:
select e1.EmployeeID,
e1.FirstName,
e1.LastName,
e1.SupervisorID,
e2.FirstName as SupervisorFirstName,
e2.LastName as SupervisorLastName
from Employee e1
left outer join Employee e2 on e1.SupervisorID ...
fatal error: malformed or corrupted AST file - Xcode
...olved the issue for me. In Xcode, go to Window->Organizer->Projects, select your project, and press the "Delete..." button next to "Derived data".
If this doesn't work, you can try to do a Product->Clean (Cmd+Shift+k).
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How to force LINQ Sum() to return 0 while source collection is empty
...word
&& l.Property.PropertyId == PropertyId)
.Select(l => l.Amount)
.DefaultIfEmpty(0)
.Sum();
This way, your query will only select the Amount field. If the collection is empty, it will return one element with the value of 0 and then the sum will ...
MYSQL Truncated incorrect DOUBLE value
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Same issue for me. A 'select * from t where id = 6503' worked okay but 'update t set a = "foo" where id = 6503' resulted in ERROR 1292 (22007): Truncated incorrect DOUBLE value: '234805557438#'. id looks like integer but was a varchar. Quoting th...
ORA-00054: resource busy and acquire with NOWAIT specified or timeout expired
...table is already locked by some query. For example, you may have executed "select for update" and have not yet committed/rollbacked and fired another select query. Do a commit/rollback before executing your query.
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