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how to add records to has_many :through association in rails
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'The best way' depends on your needs and what feels most comfortable. Confusion comes from differences ActiveRecord's behavior of the new and create methods and the << operator.
The new Method
new will not add an association record for you. You have to build the House and Agent ...
Difference between float and decimal data type
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This is what I found when I had this doubt.
mysql> create table numbers (a decimal(10,2), b float);
mysql> insert into numbers values (100, 100);
mysql> select @a := (a/3), @b := (b/3), @a * 3, @b * 3 from numbers \G
*************************** 1. row *************************...
Explain the use of a bit vector for determining if all characters are unique
...of both operands to left and right of it.
So what we have here is a hash table which is being stored in a 32 bit binary number every time the checker gets or'd ( checker |= (1 << val)) with the designated binary value of a letter its corresponding bit it is being set to true.
The character's...
What is the optimal Jewish toenail cutting algorithm?
... the fewer toes case is covered by the original algorithm (acceptable sequences for 5 toes are acceptable for 4 toes). It's those crazy extra toes that cause problems ;)
– flies
Oct 14 '11 at 14:47
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When is the init() function run?
...s this way.
A lot of the internal Go packages use init() to initialize tables and such, for example https://github.com/golang/go/blob/883bc6/src/compress/bzip2/bzip2.go#L480
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What is a 'thunk'?
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computation (similar to a closure)
a feature of some virtual function
table implementations (similar to a
wrapper function)
a mapping of machine data from one
system-specific form to another,
usually for compatibility reasons
I have usually seen it used in the third context.
http://en.wikipe...
Increment a database field by 1
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Updating an entry:
A simple increment should do the trick.
UPDATE mytable
SET logins = logins + 1
WHERE id = 12
Insert new row, or Update if already present:
If you would like to update a previously existing row, or insert it if it doesn't already exist, you can use the REPLACE synta...
How to detect Windows 64-bit platform with .NET?
... /// The function determins whether a method exists in the export
/// table of a certain module.
/// </summary>
/// <param name="moduleName">The name of the module</param>
/// <param name="methodName">The name of the method</param>
/// <returns&g...
Fast stable sorting algorithm implementation in javascript
...and a given order (asc/desc). The order of results must be consistent and stable.
16 Answers
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PostgreSQL: Is it better to use multiple databases with one schema each, or one database with multip
...LongTermStorage" and so on. "UserManagement" would then contain the "User" table, as well as all stored procedures, triggers, sequences, etc. that are needed for the user management.
Databases are entire programs, schemas are components.
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