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Find nearest latitude/longitude with an SQL query
...
SELECT latitude, longitude, SQRT(
POW(69.1 * (latitude - [startlat]), 2) +
POW(69.1 * ([startlng] - longitude) * COS(latitude / 57.3), 2)) AS distance
FROM TableName HAVING distance < 25 ORDER BY distance;
where ...
How can I tell when a MySQL table was last updated?
...e information_schema database to tell you when another table was updated:
SELECT UPDATE_TIME
FROM information_schema.tables
WHERE TABLE_SCHEMA = 'dbname'
AND TABLE_NAME = 'tabname'
This does of course mean opening a connection to the database.
An alternative option would be to "touch" a ...
Sqlite: CURRENT_TIMESTAMP is in GMT, not the timezone of the machine
...a unix
timestamp 1092941466, and compensate
for your local timezone.
SELECT datetime(1092941466, 'unixepoch', 'localtime');
That didn't look like it fit my needs, so I tried changing the "datetime" function around a bit, and wound up with this:
select datetime(timestamp, 'localtime')
That...
Random row selection in Pandas dataframe
Is there a way to select random rows from a DataFrame in Pandas.
6 Answers
6
...
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...
Android: create a popup that has multiple selection options
... Hello, can you also show how I can set actions for specific item selections? Example: I want to let the user change the app language by clicking one of those items (probably using if statement).
– Arda Çebi
Feb 7 '18 at 20:11
...
Postgres: Distinct but only for one column
...h names (having more than 1 mio. rows), but I have also many duplicates. I select 3 fields: id , name , metadata .
3 Ans...
How to remove a column from an existing table?
...lete a column from an unexisting table ;-)
BEGIN TRANSACTION
IF exists (SELECT * FROM sys.columns c
INNER JOIN sys.objects t ON (c.[object_id] = t.[object_id])
WHERE t.[object_id] = OBJECT_ID(N'[dbo].[MyTable]')
AND c.[name] = 'ColumnName')
BEGIN TRY
ALTER TABLE [dbo].[MyTable] DRO...
How to debug a single thread in Visual Studio?
...most correct and usable way is to:
Hit Ctrl+A in the breakpoints window (select all breakpoints).
Right click and select "Filter...".
Enter "ThreadId=(current thread id)".
In Visual Studio 2015 and newer, the process is similar:
Hit Ctrl+A in the breakpoints window (select all breakpoints).
Ri...
Cannot install Lxml on Mac os x 10.9
... or upgrade the commandline tool for xcode.
Try this in a terminal:
xcode-select --install
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