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SQLite table constraint - unique on multiple columns
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348
Put the UNIQUE declaration within the column definition section; working example:
CREATE TABL...
How to generate Javadoc HTML files in Eclipse?
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234
Project > Generate Javadoc....
In the Javadoc command: field, browse to find javadoc.exe (u...
How to get a value from a cell of a dataframe?
...row as a Series using iloc, and then the value using the column name:
In [3]: sub_df
Out[3]:
A B
2 -0.133653 -0.030854
In [4]: sub_df.iloc[0]
Out[4]:
A -0.133653
B -0.030854
Name: 2, dtype: float64
In [5]: sub_df.iloc[0]['A']
Out[5]: -0.13365288513107493
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Friend declaration in C++ - difference between public and private
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3 Answers
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R - Markdown avoiding package loading messages
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answered Oct 26 '12 at 16:35
Yihui XieYihui Xie
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Find an item in List by LINQ?
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IEnumerable<string> results = myList.Where(s => s == search);
3) First will return the first item which matches your criteria:
string result = myList.First(s => s == search);
Note FirstOrDefault() will behave the same, except it will return null for reference types, or the default...
TINYTEXT, TEXT, MEDIUMTEXT, and LONGTEXT maximum storage sizes
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TINYTEXT | 255 (2 8−1) bytes
TEXT | 65,535 (216−1) bytes = 64 KiB
MEDIUMTEXT | 16,777,215 (224−1) bytes = 16 MiB
LONGTEXT | 4,294,967,295 (232−1) bytes = 4 GiB
Note that the number of characters that can be stored in your column will depend on the cha...
Call a global variable inside module
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FentonFenton
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Is there a difference between “raise exception()” and “raise exception” without parenthesis?
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3 Answers
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