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count(*) vs count(column-name) - which is more correct? [duplicate]
...hich values of column is not NULL, whereas COUNT(*) counts all rows of the table.
– PureSilence
Oct 3 '19 at 7:49
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Why would introducing useless MOV instructions speed up a tight loop in x86_64 assembly?
...h was being incorrectly predicted due to aliasing in the branch prediction table
moving the branch eliminated the alias and allowed the branch to be predicted correctly
Your Core2 doesn't keep a separate history record for each conditional jump. Instead it keeps a shared history of all conditional...
How to select bottom most rows?
...olumns
FROM
(
SELECT TOP 200
columns
FROM
My_Table
ORDER BY
a_column DESC
) SQ
ORDER BY
a_column ASC
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UITableViewCell with UITextView height in iOS 7?
How can I calculate the height of an UITableViewCell with an UITextView in it in iOS 7?
12 Answers
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MySQL Orderby a number, Nulls last
...sign (-) before the column name and switch the ASC to DESC:
SELECT * FROM tablename WHERE visible=1 ORDER BY -position DESC, id DESC
It is essentially the inverse of position DESC placing the NULL values last but otherwise the same as position ASC.
A good reference is here http://troels.arvin.dk...
Pretty-print an entire Pandas Series / DataFrame
...te_yearfirst, encoding, and many many more: pandas.pydata.org/pandas-docs/stable/options.html
– nealmcb
Jan 19 '17 at 14:15
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How can I sanitize user input with PHP?
...o be guaranteed against SQL injection.
Please see my website http://bobby-tables.com/ for more about preventing SQL injection.
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Can PostgreSQL index array columns?
...e to use the array operators and the GIN-index type.
Example:
CREATE TABLE "Test"("Column1" int[]);
INSERT INTO "Test" VALUES ('{10, 15, 20}');
INSERT INTO "Test" VALUES ('{10, 20, 30}');
CREATE INDEX idx_test on "Test" USING GIN ("Column1");
-- To enforce index usage because...
How can I SELECT rows with MAX(Column value), DISTINCT by another column in SQL?
My table is:
18 Answers
18
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Can I create a One-Time-Use Function in a Script or Stored Procedure?
...s like:
create procedure #mytemp as
begin
select getdate() into #mytemptable;
end
in an SQL script, but not functions. You could have the proc store it's result in a temp table though, then use that information later in the script ..
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