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“Large data” work flows using pandas
...ns?
What will typical operations look like. E.g. do a query on columns to select a bunch of rows and specific columns, then do an operation (in-memory), create new columns, save these.
(Giving a toy example could enable us to offer more specific recommendations.)
After that processing, then what do...
List of All Locales and Their Short Codes?
...NE: "French (Niger)",
fr_RW: "French (Rwanda)",
fr_RE: "French (Réunion)",
fr_BL: "French (Saint Barthélemy)",
fr_MF: "French (Saint Martin)",
fr_SN: "French (Senegal)",
fr_CH: "French (Switzerland)",
fr_TG: "French (Togo)",
fr: "French",
ff_SN: "Fulah (Senegal)...
How to comment and uncomment blocks of code in the Office VBA Editor
...tor, go to View, Toolbars, Customise... or right click on the tool bar and select Customise...
Under the Commands tab, select the Edit menu on the left.
Then approximately two thirds of the way down there's two icons, Comment Block and Uncomment Block.
Drag and drop these onto your toolbar and th...
PostgreSQL function for last inserted ID
...e:
INSERT INTO persons (lastname,firstname) VALUES ('Smith', 'John');
SELECT currval('persons_id_seq');
The name of the sequence must be known, it's really arbitrary; in this example we assume that the table persons has an id column created with the SERIAL pseudo-type. To avoid relying on thi...
Select SQL Server database size
...
Try this one -
Query:
SELECT
database_name = DB_NAME(database_id)
, log_size_mb = CAST(SUM(CASE WHEN type_desc = 'LOG' THEN size END) * 8. / 1024 AS DECIMAL(8,2))
, row_size_mb = CAST(SUM(CASE WHEN type_desc = 'ROWS' THEN size END) ...
How can I find non-ASCII characters in MySQL?
...ng as "ASCII", but I would suggest trying a variant of a query like this:
SELECT * FROM tableName WHERE columnToCheck NOT REGEXP '[A-Za-z0-9]';
That query will return all rows where columnToCheck contains any non-alphanumeric characters. If you have other characters that are acceptable, add them ...
MySQL vs MongoDB 1000 reads
...s://github.com/webcaetano/mongo-mysql
10 rows
mysql insert: 1702ms
mysql select: 11ms
mongo insert: 47ms
mongo select: 12ms
100 rows
mysql insert: 8171ms
mysql select: 10ms
mongo insert: 167ms
mongo select: 60ms
1000 rows
mysql insert: 94813ms (1.58 minutes)
mysql select: 13ms
mongo inser...
Eclipse copy/paste entire line keyboard shortcut
...
Ctrl-Alt-Down: copies current line or selected lines to below
Ctrl-Alt-Up:: copies current line or selected lines to above
Ctrl-Shift-L: brings up a List of shortcut keys
See Windows/Preference->General->Keys.
...
What is your most productive shortcut with Vim?
...e used as subjects for other "statements."
So, one way to cut an arbitrary selection of text would be to drop a mark (I usually use 'a' as my "first" mark, 'z' as my next mark, 'b' as another, and 'e' as yet another (I don't recall ever having interactively used more than four marks in 15 years of u...
Changing selection in a select with the Chosen plugin
I'm trying to change the currently selected option in a select with the Chosen plugin.
4 Answers
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