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“Large data” work flows using pandas
...I routinely use tens of gigabytes of data in just this fashion
e.g. I have tables on disk that I read via queries, create data and append back.
It's worth reading the docs and late in this thread for several suggestions for how to store your data.
Details which will affect how you store your data,...
What's the difference between TRUNCATE and DELETE in SQL
...
General Overview
If you want to quickly delete all of the rows from a table, and you're really sure that you want to do it, and you do not have foreign keys against the tables, then a TRUNCATE is probably going to be faster than a DELETE.
Various system-specific issues have to be considered, a...
Printing Lists as Tabular Data
...e 24
Bob 19
tabulate has many options to specify headers and table format.
print(tabulate([['Alice', 24], ['Bob', 19]], headers=['Name', 'Age'], tablefmt='orgtbl'))
| Name | Age |
|--------+-------|
| Alice | 24 |
| Bob | 19 |
2. PrettyTable: https://pypi.python.org/...
Rename a table in MySQL
Renaming a table is not working in MySQL
16 Answers
16
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UITableViewCell, show delete button on swipe
How do I get the delete button to show when swiping on a UITableViewCell ? The event is never raised and the delete button never appears.
...
SQL UPDATE SET one column to be equal to a value in a related table referenced by a different column
...ver MySQL. In my case, the source and destination columns are in the same table, but record selection is based on the other table. The "SELECT" version of the query works, but the UPDTATE statement throws a syntax error at "FROM"
– 2NinerRomeo
Mar 4 '15 at 19...
SQL DROP TABLE foreign key constraint
If I want to delete all the tables in my database like this, will it take care of the foreign key constraint? If not, how do I take care of that first?
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Does the join order matter in SQL?
... neither predicate can be satisfied by a row in which all columns from one table are NULL, than to say that it's associative as long as the predicates don't involve IS NULL or 'a function that is related to nulls'. One can easily imagine a predicate that satisfies the former description but not the ...
What are the typical reasons Javascript developed on Firefox fails on IE? [closed]
...pport setting the innerHTML of col, colGroup, frameSet, html, head, style, table, tBody, tFoot, tHead, title, and tr elements. Here's a function which works around that for table-related elements:
function setHTML(elm, html) {
// Try innerHTML first
try {
elm.innerHTML = html;
} catch (exc) {
...
sqlalchemy: how to join several tables by one query?
...teger primary keys for everything, but whatever):
class User(Base):
__tablename__ = 'users'
email = Column(String, primary_key=True)
name = Column(String)
class Document(Base):
__tablename__ = "documents"
name = Column(String, primary_key=True)
author_email = Column(String,...