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How do I rename a column in a SQLite database table?
...lite.org/images/syntax/alter-table-stmt.gif
Example:
CREATE TABLE tab AS SELECT 1 AS c;
SELECT * FROM tab;
ALTER TABLE tab RENAME COLUMN c to c_new;
SELECT * FROM tab;
db-fiddle.com demo
Android Support
As of writing, Android's API 27 is using SQLite package version 3.19.
Based on the cu...
LINQ To Entities does not recognize the method Last. Really?
...e fact that eventually it has to translate that query to SQL and SQL has a SELECT TOP (in T-SQL) but not a SELECT BOTTOM (no such thing).
There is an easy way around it though, just order descending and then do a First(), which is what you did.
EDIT:
Other providers will possibly have different im...
ReactJS Two components communicating
...te is also increasing in complexity, as we need to
manage active routes, selected tabs, spinners, pagination controls,
and so on.
Managing this ever-changing state is hard. If a model can update
another model, then a view can update a model, which updates another
model, and this, in tur...
Error during installing HAXM, VT-X not working
...this, restart the computer, when the computer started then press Esc, then select the F2 if the manufacturer is dell.
Even if you have enabled the Virtualization (VT) in BIOS settings, some antivirus options prevent HAXM installation.
For example: In Avast antivirus under Settings (parameters) tab ...
Failed to enable constraints. One or more rows contain values violating non-null, unique, or foreign
...te definition in the XML and change it manually.
Remove primary keys from select lists in table adapters if they are not related to the data being returned.
Run your query in SQL Management Studio and ensure there are not duplicate records being returned. Duplicate records can generate duplicate p...
What does the “>” (greater-than sign) CSS selector mean?
...etimes mistakenly called the direct descendant combinator.1
That means the selector div > p.some_class only selects paragraphs of .some_class that are nested directly inside a div, and not any paragraphs that are nested further within.
An illustration:
div > p.some_class {
background:...
Is it safe to remove selected keys from map within a range loop?
How can one remove selected keys from a map?
Is it safe to combine delete() with range, as in the code below?
4 Answers
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How to take column-slices of dataframe in pandas
...e .loc
See the deprecation in the docs
.loc uses label based indexing to select both rows and columns. The labels being the values of the index or the columns. Slicing with .loc includes the last element.
Let's assume we have a DataFrame with the following columns:
foo, bar, quz, ant, cat, ...
Convert a string to int using sql query
...
You could use CAST or CONVERT:
SELECT CAST(MyVarcharCol AS INT) FROM Table
SELECT CONVERT(INT, MyVarcharCol) FROM Table
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What CSS selector can be used to select the first div within another div
...
Can you tell me how to select all div except first/last div?
– Tân
Jul 5 '16 at 9:17
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