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What is a good reason to use SQL views?
...one extra column active.
If your system(s) have gazillion queries that do SELECT whatever FROM T_OLD WHERE whatever, you have two choices for the roll-out:
1) Cold Turkey - Change the DB, and at the same time, change, test and release numerous pieces of code which contained said query. VERY hard t...
In PHP with PDO, how to check the final SQL parametrized query? [duplicate]
..... and finally EXECUTE ....
You won't be able to get some SQL string like SELECT * FROM ..., even if it would produce equivalent results, because no such query was ever actually sent to the database.
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In PHP what does it mean by a function being binary-safe?
...on which expects null-terminated strings, so if the string contains a null character, the function would ignore anything after it.
This is relevant because PHP does not cleanly separate string and binary data.
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What's the best way to join on the same table twice?
...tiple times or using subqueries etc.
I would just clean things up a bit:
SELECT t.PhoneNumber1, t.PhoneNumber2,
t1.SomeOtherFieldForPhone1, t2.someOtherFieldForPhone2
FROM Table1 t
JOIN Table2 t1 ON t1.PhoneNumber = t.PhoneNumber1
JOIN Table2 t2 ON t2.PhoneNumber = t.PhoneNumber2
What i did:...
Visual Studio: How do I show all classes inherited from a base class?
...Resharper 9.2, on any type in source code, rt-click "Find Usage Advanced", select Find="Derived" and Scope="Solutions and Libraries".
For example, to find all inheritors (both in the library and your code) of some base class in an included DLL from any vendor, declare a variable in your code with th...
Postgres NOT in array
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SELECT COUNT(*) FROM "messages" WHERE NOT (3 = ANY (recipient_ids))
You can always negate WHERE (condition) with WHERE NOT (condition)
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Use LINQ to get items in one List, that are not in another List
...erride the equality:
var excludedIDs = new HashSet<int>(peopleList1.Select(p => p.ID));
var result = peopleList2.Where(p => !excludedIDs.Contains(p.ID));
This variant does not remove duplicates.
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How to select rows with one or more nulls from a pandas DataFrame without listing columns explicitly
... 0.0 NaN 0.0
3 0.0 1.0 2.0 3.0
4 NaN 0.0 NaN NaN
If you want to select the rows that have two or more columns with null value, you run the following:
>>> qty_of_nuls = 2
>>> df.iloc[df[(df.isnull().sum(axis=1) >=qty_of_nuls)].index]
0 1 2 3
1 0.0 NaN 0...
What does $_ mean in PowerShell?
...dItem | Add-Member -Type NoteProperty -Name Bar -Value $_.Name -PassThru | Select Bar ... Well, it can work if you have a $_ in the scope where you're executing that pipeline. But that's very different from what you usually mean when trying to write something like that.
– Joey
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Difference between string object and string literal [duplicate]
...fference. s1 will refer to an interned String object. This means, that the character sequence "abcde" will be stored at a central place, and whenever the same literal "abcde" is used again, the JVM will not create a new String object but use the reference of the cached String.
s2 is guranteed to be...