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How do you convert a byte array to a hexadecimal string, and vice versa?
...)
Text: 718,380.63 (1.0X faster)
Sentence: 39.71 (1.0X faster)
Lookup tables have taken the lead over byte manipulation. Basically, there is some form of precomputing what any given nibble or byte will be in hex. Then, as you rip through the data, you simply look up the next portion to see what...
How do I expire a PHP session after 30 minutes?
...>
<html>
<form name="form1" method="post">
<table>
<tr>
<td>Username</td>
<td><input type="text" name="text"></td>
</tr>
<tr>
<td&g...
Summarizing multiple columns with dplyr? [duplicate]
... 2.87
#> 3 3 2.85 2.95 2.95 3.06
Also don't forget about data.table (use keyby to sort sort groups):
library(data.table)
setDT(df)[, lapply(.SD, mean), keyby = grp]
#> grp a b c d
#> 1: 1 3.079412 2.979412 2.979412 2.914706
#> 2: 2 3.029126 3....
How to remove not null constraint in sql server using query
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ALTER TABLE YourTable ALTER COLUMN YourColumn columnType NULL
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Why does MYSQL higher LIMIT offset slow the query down?
Scenario in short: A table with more than 16 million records [2GB in size]. The higher LIMIT offset with SELECT, the slower the query becomes, when using ORDER BY *primary_key*
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In a storyboard, how do I make a custom cell for use with multiple controllers?
...he goal is to have those be re-usable throughout the app (ie, in any of my tableview controllers).
6 Answers
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What are the applications of binary trees?
...nary Tries - Used in almost every high-bandwidth router for storing router-tables.
Hash Trees - used in p2p programs and specialized image-signatures in which a hash needs to be verified, but the whole file is not available.
Heaps - Used in implementing efficient priority-queues, which in turn are u...
LINQ Join with Multiple Conditions in On Clause
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This works fine for 2 tables. I have 3 tables and on clause has to link 2 conditions from 3 tables.
My code:
from p in _dbContext.Products
join pv in _dbContext.ProductVariants on p.ProduktId equals pv.ProduktId
join jpr in leftJoinQuery
on new {...
Conversion failed when converting date and/or time from character string while inserting datetime
I was trying to create a table as follows,
15 Answers
15
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How to encrypt/decrypt data in php?
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Foreword
Starting with your table definition:
- UserID
- Fname
- Lname
- Email
- Password
- IV
Here are the changes:
The fields Fname, Lname and Email will be encrypted using a symmetric cipher, provided by OpenSSL,
The IV field will store the init...