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Best Practices: Salting & peppering passwords?
...n order for it to be considered secure. Additionally, it has to be implementable in a maintainable way. The most secure system that can't be maintained is considered insecure (because if any part of that security breaks down, the entire system falls apart).
And peppers fit neither the provable or t...
NoSQL Use Case Scenarios or WHEN to use NoSQL [closed]
...L DBs often lack the ability to perform atomic operations across multiple "tables".
You really need to look at and understand what the various types of NoSQL stores are, and how they go about providing scalability/data security etc. It's difficult to give an across-the-board answer as they really ...
Why all the Active Record hate? [closed]
...problem that I see with Active Records is, that it's always just about one table
Code:
class Person
belongs_to :company
end
people = Person.find(:all, :include => :company )
This generates SQL with LEFT JOIN companies on companies.id = person.company_id, and automatically generates assoc...
The Role Manager feature has not been enabled
...thod will run just fine (if you haven't messed elsewhere) and create a few tables in your Database;
Press Ctrl+W+L to open the Server Explorer and you should be able to check in Data Connections > DefaultConnection > Tables the Roles and UsersInRoles tables among the newly created tables!
...
Advantages and disadvantages of GUID / UUID database keys
...
@Matt Sheppard:
Say you have a table of customers. Surely you don't want a customer to exist in the table more than once, or lots of confusion will happen throughout your sales and logistics departments (especially if the multiple rows about the customer c...
SQL join on multiple columns in same tables
... subqueries, but I'm having trouble joining columns together from the same tables. I tried:
2 Answers
...
querySelector and querySelectorAll vs getElementsByClassName and getElementById in JavaScript
...ements are live or static.
These concepts are summarized in the following table.
Function | Live? | Type | Time Complexity
querySelector | N | Element | O(n)
querySelectorAll | N | NodeList | O(n)
getElementById | Y | Element...
Aggregate / summarize multiple variables per group (e.g. sum, mean)
...
Using the data.table package, which is fast (useful for larger datasets)
https://github.com/Rdatatable/data.table/wiki
library(data.table)
df2 <- setDT(df1)[, lapply(.SD, sum), by=.(year, month), .SDcols=c("x1","x2")]
setDF(df2) # con...
初窥InnoDB的Memcached插件 - 大数据 & AI - 清泛网 - 专注C/C++及内核技术
...件所需要的配置信息：
mysql> USE innodb_memcache
mysql> SHOW TABLES;
+---------------------------+
| Tables_in_innodb_memcache |
+---------------------------+
| cache_policies |
| config_options |
| containers |
+---------------------------+
...
Is storing a delimited list in a database column really that bad?
...m in a comma separated list of values stored in one column of the database table.
10 Answers
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