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Does the 'mutable' keyword have any purpose other than allowing the variable to be modified by a con
...able of a class with the mutable keyword. As far as I can see it simply allows you to modify a variable in a const method:
...
How does Rails keep track of which migrations have run for a database?
...
Rails creates a table in your database called schema_migrations to keep track of which migrations have run.
The table contains a single column, version. When Rails runs a migration, it takes the leading digits in the migration's file name and inserts a row for that "version",...
How do HashTables deal with collisions?
...lookups in hash tables very slow.
Option 2: If the hash table entries are all full then the hash table can increase the number of buckets that it has and then redistribute all the elements in the table. The hash function returns an integer and the hash table has to take the result of the hash funct...
How to get memory available or used in C#
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It should probably be noted that a call to GetCurrentProcess will itself allocate quite a lot of resources. Call Dispose on the returned process when done, or wrap the whole code in a "using" scope.
– Mathias Lykkegaard Lorenzen
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Git: “Not currently on any branch.” Is there an easy way to get back on a branch, while keeping the
... hash of last commit. Checkout the branch you wish to be at, and git merge _hash_
– Daniel
May 31 '12 at 13:31
BE REAL...
Creating a new user and password with Ansible
... parameter.
There you'll see that your password must be hashed.
- hosts: all
user: root
vars:
# created with:
# python -c 'import crypt; print crypt.crypt("This is my Password", "$1$SomeSalt$")'
password: $1$SomeSalt$UqddPX3r4kH3UL5jq5/ZI.
tasks:
- user: name=tset password={...
How to do 3 table JOIN in UPDATE query?
... it had something to do with ON UPDATE CURRENT_TIMESTAMP, I just added manually the update and it fixed it, just saying if it happens to anyone else
– eric.itzhak
Jun 6 '16 at 13:35
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Make anchor link go some pixels above where it's linked to
... window.scrollTo(window.scrollX, window.scrollY - 100);
});
This will allow the browser to do the work of jumping to the anchor for us and then we will use that position to offset from.
EDIT 1:
As was pointed out by @erb, this only works if you are on the page while the hash is changed. Enter...
What are the advantages of using a schema-free database like MongoDB compared to a relational databa
...ire several tables to properly represent in a relational db. This is especially useful if your data is immutable.
Deep query-ability. MongoDB supports dynamic queries on documents using a document-based query language that's nearly as powerful as SQL.
No schema migrations. Since MongoDB is schema-...
Regular expression \p{L} and \p{N}
...This syntax is specific for modern Unicode regex implementation, which not all interpreters recognize. You can safely replace \p{L} by {a-zA-Z} (ascii notation) or {\w} (perl/vim notation); and \p{N} by {0-9} (ascii) or {\d} (perl/vim). If you want to match all of them, just do: {a-zA-Z0-9}+ or {\w\...