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Common MySQL fields and their appropriate data types
I am setting up a very small MySQL database that stores, first name, last name, email and phone number and am struggling to find the 'perfect' datatype for each field. I know there is no such thing as a perfect answer, but there must be some sort of common convention for commonly used fields such as...
Difference between BeautifulSoup and Scrapy crawler?
...ter extraction. For example we can configure pipeline to push data to your mysql server.
Cookies: scrapy automatically handles cookies for us.
etc.
TLDR: scrapy is a framework that provides everything that one might
need to build large scale crawls. It provides various features that
hide c...
SQLite INSERT - ON DUPLICATE KEY UPDATE (UPSERT)
MySQL has something like this:
5 Answers
5
...
MySQL COUNT DISTINCT
....new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f5737628%2fmysql-count-distinct%23new-answer', 'question_page');
}
);
Post as a guest
Name
...
mysql :: insert into table, data from another table?
...use above query if we want to copy data from one table to another table in mysql
Here source and destination table are same, we can use different tables also.
Few columns we are not copying like style_id and is_deleted so we selected them hard coded from another table
Table we used in source also ...
Laravel migration: unique key is too long, even if specified
...allows to store long key indexes.
Server settings (by default included in MySQL 5.7.7+ / MariaDB 10.2.2+):
[mysqld]
# default character set and collation
collation-server = utf8mb4_unicode_ci
character-set-server = utf8mb4
# utf8mb4 long key index
innodb_large_prefix = 1
innodb_file_format = barr...
What is the fastest/most efficient way to find the highest set bit (msb) in an integer in C?
...zeof(uint32_t));
return (tmp>>20)-1023;
Or in C99 and later, use a union {double d; uint32_t u[2];};. But note that in C++, union type punning is only supported on some compilers as an extension, not in ISO C++.
This will usually be slower than a platform-specific intrinsic for a leading...
What is an index in SQL?
...
An index is used to speed up searching in the database. MySQL have some good documentation on the subject (which is relevant for other SQL servers as well):
http://dev.mysql.com/doc/refman/5.0/en/mysql-indexes.html
An index can be used to efficiently find all rows matching some c...
How to find all tables that have foreign keys that reference particular table.column and have values
...
For what kind of DB is this useful? MySql?
– Cirelli94
Jan 9 '18 at 10:56
...
Oracle PL/SQL - How to create a simple array variable?
...
BULK COLLECT INTO arrayvalues
FROM (select 'Matt' m_value from dual union all
select 'Joanne' from dual union all
select 'Robert' from dual
)
;
--
FOR i IN 1 .. arrayvalues.COUNT
LOOP
dbms_output.put_line(arrayvalues(i)||' is my friend');
END LO...