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Quick easy way to migrate SQLite3 to MySQL? [closed]
...nes starting with:
BEGIN TRANSACTION
COMMIT
sqlite_sequence
CREATE UNIQUE INDEX
are not used in MySQL
SQLite uses CREATE TABLE/INSERT INTO "table_name" and MySQL uses CREATE TABLE/INSERT INTO table_name
MySQL doesn't use quotes inside the schema definition
MySQL uses single quotes for strings ins...
Storing sex (gender) in database
... a need to port.
Conclusion
I would use Option 2: CHAR(1).
Addendum
An index on the gender column likely would not help because there's no value in an index on a low cardinality column. Meaning, there's not enough variety in the values for the index to provide any value.
...
How to avoid passing parameters everywhere in play2?
...
Then in your actions you’ll be able to just write the following:
def index = Action {
Ok(views.html.index())
}
def index2 = Action {
Ok(views.html.index2())
}
You can find more information about this approach in this blog post and in this code sample.
Update: A nice blog post demonstra...
How to get a variable value if variable name is stored as string?
...our script using /bin/sh? If so, try using /bin/bash instead. From Debian Squeeze onwards, /bin/sh was changed to be a symlink for dash instead of bash. dash doesn't support this particular syntax and will output a Bad substitution error.
– Phil Ross
Aug 8 '13 ...
How to COUNT rows within EntityFramework without loading contents?
...ce SQL Server really can't do anything but do a full table scan (clustered index scan).
Sometimes, it's good enough to know an approximate number of rows from the database, and in such a case, a statement like this might suffice:
SELECT
SUM(used_page_count) * 8 AS SizeKB,
SUM(row_count) ...
HTTP error 403 in Python 3 Web Scraping
...ily detected). Try setting a known browser user agent with:
from urllib.request import Request, urlopen
req = Request('http://www.cmegroup.com/trading/products/#sortField=oi&sortAsc=false&venues=3&page=1&cleared=1&group=1', headers={'User-Agent': 'Mozilla/5.0'})
webpage = urlop...
Best way to test if a row exists in a MySQL table
...on in the comments, that in this situation:
SELECT 1 FROM my_table WHERE *indexed_condition* LIMIT 1
Is superior to:
SELECT * FROM my_table WHERE *indexed_condition* LIMIT 1
This is because the first query can be satisfied by the index, whereas the second requires a row look up (unless possibl...
How to extract a floating number from a string [duplicate]
...ng stuff in the following answer of mine that I did for a previous similar question:
https://stackoverflow.com/q/5929469/551449
In this answer, I proposed a pattern that allows a regex to catch any kind of number and since I have nothing else to add to it, I think it is fairly complete
...
MySQL case insensitive select
...e, comparisons are case-insensitive. You need to understand collations and indexes and configure those properly - using string transformations like LOWER() or an arbitrary COLLATE clause can completely bypass an index, and over time, as your table grows, this can have drastic performance implication...
How do I get the base URL with PHP?
...Try this:
<?php echo "http://" . $_SERVER['SERVER_NAME'] . $_SERVER['REQUEST_URI']; ?>
Learn more about the $_SERVER predefined variable.
If you plan on using https, you can use this:
function url(){
return sprintf(
"%s://%s%s",
isset($_SERVER['HTTPS']) && $_SERVER['HTTP...