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Best way to store time (hh:mm) in a database
...t a glance and performing calculations on them are straightforward.
E.g.
SELECT DATEDIFF(MINUTE, event_start, event_end)
ISO8601 date standard
If using SQLite then you don't have this, so instead use a Text field and store it in ISO8601 format eg.
"2013-01-27T12:30:00+0000"
Notes:
This use...
Chrome developer tools: View Console and Sources views in separate views/vertically tiled?
...Open the three-dot menu in the upper right corner of the dev tools window.
Select 'Settings'.
"General" tab --> "Appearance" section
"Panel Layout"
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Reverting part of a commit with git
... for reverting whole commits. You can use git checkout -p to interactively select bits to revert.
– mipadi
Mar 31 '17 at 18:52
1
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Why does SSL handshake give 'Could not generate DH keypair' exception?
...DHE_.... The later would happen if I added BouncyCastle. If TLS_ECDHE_ was selected, MOST OF the time it worked, but not ALWAYS, so adding even BouncyCastle provider was unreliable (failed with same error, every other time or so). I guess somewhere in the Sun SSL implementation sometimes it choose D...
What is the difference between tinyint, smallint, mediumint, bigint and int in MySQL?
...nyint data types. Values are inserted into each column and returned in the SELECT statement.
CREATE TABLE dbo.MyTable
(
MyBigIntColumn bigint
,MyIntColumn int
,MySmallIntColumn smallint
,MyTinyIntColumn tinyint
);
GO
INSERT INTO dbo.MyTable VALUES (9223372036854775807, 214483647,32767,255);...
Exact difference between CharSequence and String in java [duplicate]
...SR 378 again…
Using "one-dimensional" string literals.
String query = "SELECT \"EMP_ID\", \"LAST_NAME\" FROM \"EMPLOYEE_TB\"\n" +
"WHERE \"CITY\" = 'INDIANAPOLIS'\n" +
"ORDER BY \"EMP_ID\", \"LAST_NAME\";\n";
Using a "two-dimensional" block of text
String query =...
Is there a timeout for idle PostgreSQL connections?
...ement an idle connection reaper. Have a cron job run something like this:
SELECT pg_terminate_backend(pid)
FROM pg_stat_activity
WHERE datname = 'regress'
AND pid <> pg_backend_pid()
AND state = 'idle'
AND state_change < current_timestamp - INTERVAL '5' MINUTE;
...
Summarizing multiple columns with dplyr? [duplicate]
...
I mean, the behavior like in select would be great: summarize(df, a:c, d=paste(d, collaspe =',' ) . Just want to put more original columns in for reference
– biocyberman
Aug 8 '15 at 17:28
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Can I have multiple primary keys in a single table?
...hese practices, but there is nothing in the relational model that requires selecting a primary key among the candidate keys.
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How do I force Postgres to use a particular index?
...d, client_id, date, and description. You want to run the following query:
SELECT client_id, SUM(amount)
FROM transactions
WHERE date >= 'yesterday'::timestamp AND date < 'today'::timestamp AND
description = 'Refund'
GROUP BY client_id
PostgreSQL may choose to use the index transaction...