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How can I generate an MD5 hash?
... “LATIN1” != “ASCII” (or “US-ASCII”). ASCII is a 7-bit character set, Latin1 is an 8-bit character set. They are not the same.
– Bombe
Jan 7 '09 at 7:57
8
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How can I escape a double quote inside double quotes?
...
Use a backslash:
echo "\"" # Prints one " character.
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How to find gaps in sequential numbering in mysql?
...r
Here's version that works on table of any size (not just on 100 rows):
SELECT (t1.id + 1) as gap_starts_at,
(SELECT MIN(t3.id) -1 FROM arrc_vouchers t3 WHERE t3.id > t1.id) as gap_ends_at
FROM arrc_vouchers t1
WHERE NOT EXISTS (SELECT t2.id FROM arrc_vouchers t2 WHERE t2.id = t1.id + ...
How to select only date from a DATETIME field in MySQL?
...e a table in the MySQL database that is set up with DATETIME . I need to SELECT in this table only by DATE and excluding the time.
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What does it mean by select 1 from table?
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SELECT 1 FROM TABLE_NAME means, "Return 1 from the table". It is pretty unremarkable on its own, so normally it will be used with WHERE and often EXISTS (as @gbn notes, this is not necessarily best practice, it is, however, c...
How to remove all whitespace from a string?
...paces before, after and in between
" \u2190 \u2192 ", # contains unicode chars
paste0( # varied whitespace
whitespace,
"x",
whitespace,
"y",
whitespace,
collapse = ""
),
NA # missing
)
## [1] " x y "
#...
What is a regular expression for a MAC Address?
... The second will incorrectly match strings which contain non-hex characters such as g.
– Binary Phile
Feb 25 '15 at 15:32
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MySQL INNER JOIN select only one row from second table
...have multiple associated payments in the payments table. I would like to select all users who have payments, but only select their latest payment. I'm trying this SQL but i've never tried nested SQL statements before so I want to know what i'm doing wrong. Appreciate the help
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is it possible to select EXISTS directly as a bit?
...workaround.
If you must return a conditional bit 0/1 another way is to:
SELECT CAST(
CASE WHEN EXISTS(SELECT * FROM theTable where theColumn like 'theValue%') THEN 1
ELSE 0
END
AS BIT)
Or without the cast:
SELECT
CASE
WHEN EXISTS( SELECT 1 FROM theTable WHERE theColumn LI...
MySQL: Insert record if not exists in table
...oDB;
Insert a record:
INSERT INTO table_listnames (name, address, tele)
SELECT * FROM (SELECT 'Rupert', 'Somewhere', '022') AS tmp
WHERE NOT EXISTS (
SELECT name FROM table_listnames WHERE name = 'Rupert'
) LIMIT 1;
Query OK, 1 row affected (0.00 sec)
Records: 1 Duplicates: 0 Warnings: 0
...