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Installing R on Mac - Warning messages: Setting LC_CTYPE failed, using “C”
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In my system (OS X 10.11 El Capitán) I have environment variables LANG and LC_ALL set to en_US.UTF-8 for my terminal (in the ~/.bash_profile file), and command line R does not display those warning messages; but R Studio does. Fo...
How do I check if an index exists on a table field in MySQL?
...ame) full_path_schema, y.name index_name
FROM information_schema.INNODB_SYS_TABLES as x
JOIN information_schema.INNODB_SYS_INDEXES as y on x.TABLE_ID = y.TABLE_ID
WHERE x.name = 'your_schema'
and y.name = 'your_column') d on concat(a.table_schema, '/', a.table_name, '/', a.column_name) ...
Java: How to convert List to Map
... have conversation with a colleague about what would be the optimal way to convert List to Map in Java and if there any specific benefits of doing so.
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Drop all tables whose names begin with a certain string
... TableName,
so.object_id AS TableID,
0 AS Ordinal
FROM sys.objects AS so
WHERE so.type = 'U'
AND so.is_ms_Shipped = 0
AND OBJECT_NAME(so.object_id)
LIKE 'MyPrefix%'
UNION ALL
SELECT OBJECT_SCHEMA_NAME(so.object_id) AS SchemaName,
OBJEC...
How to re-raise an exception in nested try/except blocks?
...ument form of raise:
try:
something()
except SomeError:
t, v, tb = sys.exc_info()
try:
plan_B()
except AlsoFailsError:
raise t, v, tb
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How to convert/parse from String to char in java?
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If your string contains exactly one character the simplest way to convert it to a character is probably to call the charAt method:
char c = s.charAt(0);
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A numeric string as array key in PHP
...se a numeric string like "123" as a key in a PHP array, without it being converted to an integer?
11 Answers
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multiprocessing: sharing a large read-only object between processes?
...y.
The child parts are pleasant to write because each child simply reads sys.stdin.
The parent has a little bit of fancy footwork in spawning all the children and retaining the pipes properly, but it's not too bad.
Fan-in is the opposite structure. A number of independently running processes ...
What is the correct SQL type to store a .Net Timespan with values > 24:00:00?
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I'd probably convert the ticks into a time object like this: SELECT CAST(DATEADD(MILLISECOND, @Ticks/CAST(10000 AS BIGINT), '1900-01-01') AS TIME). The '1900-01-01' date doesn't matter, of course, it's just the third variable required by ...
Unable to cast object of type 'System.DBNull' to type 'System.String`
... the first case @Alexander mentions -not matching any row- you can rely on Convert.ToString or any other Convert method if you are fine with the value they return when converting from null: empty string for strings, 0 for numeric values, false for boolean, MinValue for DateTime... msdn.microsoft.com...