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Difference between . and : in Lua
...:method(arg) retrieves object only once. If object is a global, upvalue or table field, then : is faster than .. . is never faster than :.
– negamartin
Nov 5 '16 at 8:08
add a...
How to delete a column from a table in MySQL
Given the table created using:
8 Answers
8
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✔ Checkmark selected row in UITableViewCell
I am an iOS development newbie. I want to add a checkmark to my UITableViewCell when it is selected. The checkmark should be removed when another row is selected. How would I do this?
...
psycopg2: insert multiple rows with one query
...("(%s,%s,%s,%s,%s,%s,%s,%s,%s)", x) for x in tup)
cur.execute("INSERT INTO table VALUES " + args_str)
and 2 minutes when using this method:
cur.executemany("INSERT INTO table VALUES(%s,%s,%s,%s,%s,%s,%s,%s,%s)", tup)
sh...
Postgres manually alter sequence
... ALTER SEQUENCE [sequence] RESTART WITH (SELECT MAX(col) from table); does not work, whereas SELECT setval('sequence', (SELECT (MAX(col) from table), TRUE); does work. I get a syntax error. (Postgres 9.4)
– NuclearPeon
Jul 21 '18 at 1:35
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Condition within JOIN or WHERE
...in join improve performance for large amount of data with properly indexed tables.
– Shahdat
Oct 6 '16 at 15:13
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How do I set the time zone of MySQL?
...ed timezones like 'Europe/Helsinki' means that you have to have a timezone table properly populated.)
Keep in mind that +02:00 is an offset. Europe/Berlin is a timezone (that has two offsets) and CEST is a clock time that corresponds to a specific offset.
@@session.time_zone variable
SELECT @@ses...
What do linkers do?
...ood" when you convert a source file (such as a C or C++ file) into an executable file (an executable file is a file that can be executed on your machine or someone else's machine running the same machine architecture).
Under the hood, when a program is compiled, the compiler converts the source fi...
TSQL - How to use GO inside of a BEGIN .. END block?
...t using SET NOEXEC.
IF not whatever
BEGIN
SET NOEXEC ON;
END
ALTER TABLE dbo.EMPLOYEE ADD COLUMN EMP_IS_ADMIN BIT NOT NULL
GO
UPDATE dbo.EMPLOYEE SET EMP_IS_ADMIN = whatever
SET NOEXEC OFF;
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How can I mix LaTeX in with Markdown? [closed]
...eat. I even do some preprocessing on the Markdown so I can do things like tables. But this term I'm teaching a class with a lot of math, and I'd love to be able to put LaTeX formulas with Markdown, something like this:
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