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What's the difference between ASCII and Unicode?
...as parity bit.
This was relevant years ago.
Most ASCII characters are printable characters of the alphabet such as abc, ABC, 123, ?&!, etc. The others are control characters such as carriage return, line feed, tab, etc.
See below the binary representation of a few characters in ASCII:
0100101 -...
What is a NullReferenceException, and how do I fix it?
...that C# has the concept of nullable datatypes for variables (like database tables can have nullable fields) - you can assign null to them to indicate there is no value stored in it, for example int? a = null; where the question mark indicates it is allowed to store null in variable a. You can check ...
How to read a CSV file into a .NET Datatable
How can I load a CSV file into a System.Data.DataTable , creating the datatable based on the CSV file?
22 Answers
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Is there a way to get rid of accents and convert a whole string to regular letters?
...(string, Normalizer.Form.NFD);
// or Normalizer.Form.NFKD for a more "compatable" deconstruction
This will separate all of the accent marks from the characters. Then, you just need to compare each character against being a letter and throw out the ones that aren't.
string = string.replaceAll("[...
Array to String PHP?
...e a DB is so you can accomplish work like this trivially. You don't need a table to store arrays, you need a table that you can represent as an array.
Example:
id | word
1 | Sports
2 | Festivals
3 | Classes
4 | Other
You would simply select the data from the table with SQL, rather than have ...
What is the difference between join and merge in Pandas?
...e the main differences between df.join() and df.merge():
lookup on right table: df1.join(df2) always joins via the index of df2, but df1.merge(df2) can join to one or more columns of df2 (default) or to the index of df2 (with right_index=True).
lookup on left table: by default, df1.join(df2) uses...
PostgreSQL - fetch the row which has the Max value for a column
I'm dealing with a Postgres table (called "lives") that contains records with columns for time_stamp, usr_id, transaction_id, and lives_remaining. I need a query that will give me the most recent lives_remaining total for each usr_id
...
How do you connect to multiple MySQL databases on a single webpage?
...ery database 1 pass the first link identifier:
mysql_query('select * from tablename', $dbh1);
and for database 2 pass the second:
mysql_query('select * from tablename', $dbh2);
If you do not pass a link identifier then the last connection created is used (in this case the one represented by $d...
Frequency table for a single variable
One last newbie pandas question for the day: How do I generate a table for a single Series?
4 Answers
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MySQL and GROUP_CONCAT() maximum length
...T SESSION group_concat_max_len = 1000000;
select group_concat(column) from table group by column
You can do this even in sharing hosting, but when you use an other session, you need to repeat the SET SESSION command.
share...