大约有 47,000 项符合查询结果(耗时:0.0569秒) [XML]
Find all files with name containing string
... command that will return files from the current directory which contain a string in the filename. I have seen locate and find commands that can find files beginning with something first_word* or ending with something *.jpg .
...
Assign null to a SqlParameter
... The suggestion looked promising so I tried "System.Data.SqlTypes.SqlString.Null" but it doesn't work. It puts actual string of "Null" ('N', 'u', 'l', 'l') into the field instead leaving it blank with true (null). However, the old 2010 "accepted answer" that uses cast with (object) ?? DBNull...
Reset auto increment counter in postgres
...ated the table product with an id column, then the sequence is not simply called product, but rather product_id_seq (that is, ${table}_${column}_seq).
This is the ALTER SEQUENCE command you need:
ALTER SEQUENCE product_id_seq RESTART WITH 1453
You can see the sequences in your database using the...
Extract subset of key-value pairs from Python dictionary object?
...
If you're using Python 3, and you only want keys in the new dict that actually exist in the original one, you can use the fact to view objects implement some set operations:
{k: bigdict[k] for k in bigdict.keys() & {'l', 'm', 'n'}}
...
Java optional parameters
...s to simulate optional parameters in Java:
Method overloading.
void foo(String a, Integer b) {
//...
}
void foo(String a) {
foo(a, 0); // here, 0 is a default value for b
}
foo("a", 2);
foo("a");
One of the limitations of this approach is that it doesn't work if you have two optional ...
How to delete migration files in Rails 3
...
I usually:
Perform a rake db:migrate VERSION=XXX on all environments, to the version before the one I want to delete.
Delete the migration file manually.
If there are pending migrations (i.e., the migration I removed was not the...
How to add title to subplots in Matplotlib?
...
A shorthand answer assuming
import matplotlib.pyplot as plt:
plt.gca().set_title('title')
as in:
plt.subplot(221)
plt.gca().set_title('title')
plt.subplot(222)
etc...
Then there is no need for superfluous variables.
...
string.IsNullOrEmpty(string) vs. string.IsNullOrWhiteSpace(string)
Is use of string.IsNullOrEmpty(string) when checking a string considered as bad practice when there is string.IsNullOrWhiteSpace(string) in .NET 4.0 and above?
...
How can I start PostgreSQL server on Mac OS X?
...
The Homebrew package manager includes launchctl plists to start automatically. For more information, run brew info postgres.
Start manually
pg_ctl -D /usr/local/var/postgres start
Stop manually
pg_ctl -D /usr/local/var/postgres stop
Start automatically
"To have launchd start postgresql now and res...
How to find out which version of the .NET Framework an executable needs to run?
... select-object -ExpandProperty Value |
select-string -Pattern '.NET')
Write-Output "$filename,$version"
}
provides the following result;
Note that the result extracted the .NET version for the exe files in that folder, but it will also do the same for a dll.
...
