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Connect to a heroku database with pgadmin
...ase (postgres instance in Heroku), do the following:
Login to Heroku, and select the application in which you have the database
Select the Resources tab and then click on "Heroku Postgres Ad-on" (see below). This will open up a new tab.
Select the Settings tab and then click on "View Credential...
get list of pandas dataframe columns based on data type
...
If you are just selecting columns by data type, then this answer is obsolete. Use select_dtypes instead
– Ted Petrou
Nov 3 '17 at 16:58
...
Jquery If radio button is checked
...' of "appended" to the 'appended' element
appended.id = 'appended';
// 1. selects '<input type="radio" />' elements with the 'name' attribute of 'postage'
// 2. assigns the onChange/onchange event handler
$('input:radio[name="postage"]').change(
function(){
// checks that the cli...
MySQL ON DUPLICATE KEY - last insert id?
...LAST_INSERT_ID(3000)) ON DUPLICATE KEY UPDATE id = LAST_INSERT_ID(id + 1);
SELECT LAST_INSERT_ID();
If the prefix exists, it will increment it and populate last_insert_id.
If the prefix does not exist, it will insert the prefix with the value 3000 and populate last_insert_id with 3000.
...
Rails ActiveRecord date between
...ne day. The field is part of the standard timestamps, is created_at . The selected date is coming from a date_select .
11...
#1071 - Specified key was too long; max key length is 767 bytes
...o 3072 bytes.
You also have to be aware that if you set an index on a big char or varchar field which is utf8mb4 encoded, you have to divide the max index prefix length of 767 bytes (or 3072 bytes) by 4 resulting in 191. This is because the maximum length of a utf8mb4 character is four bytes. For a...
“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...
Good Hash Function for Strings
...ng it might be a good idea to sum up the unicode values for the first five characters in the string (assuming it has five, otherwise stop where it ends). Would that be a good idea, or is it a bad one?
...
How can I concatenate two arrays in Java?
...itive arrays:
Booleans.concat(first, second)
Bytes.concat(first, second)
Chars.concat(first, second)
Doubles.concat(first, second)
Shorts.concat(first, second)
Ints.concat(first, second)
Longs.concat(first, second)
Floats.concat(first, second)
...
Find CRLF in Notepad++
...h processes:
Simple search (Ctrl+F), Search Mode = Normal
You can select an EOL in the editing window.
Just move the cursor to the end of the line, and type Shift+Right Arrow.
or, to select EOL with the mouse, start just at the line end and drag to the start of the next line; dr...