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Maximum length for MD5 input/output
...ngs use an array internally, therefore, a string can only contain (2^31)-1 characters (or less, depending on the heap size).That would also be your maximum input for the MD5 function in Java. But pure theoretically, the MD5 function could process indeed an input of arbitrary length. ;)
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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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What is the reason not to use select *?
...eople claim that you should specifically name each column you want in your select query.
20 Answers
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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
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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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How to sort an array of integers correctly
...sn't. Confusing for other developers to read your code, just to save a few chars. Don't depend on side effects - code with purpose!
– bambery
Dec 2 '16 at 5:03
14
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Word-wrap in an HTML table
...uld potentially preprocess the text and wrap only long words (say, > 40 chars) in the <span>.
– nornagon
Jun 2 '11 at 8:30
9
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Getting the minimum of two values in SQL
...led OwedPast . They are both results of some subqueries in SQL. How can I select the smaller of the two and return it as a value titled PaidForPast ?
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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...
Difference between Select Unique and Select Distinct
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SELECT UNIQUE is old syntax supported by Oracle's flavor of SQL. It is synonymous with SELECT DISTINCT.
Use SELECT DISTINCT because this is standard SQL, and SELECT UNIQUE is non-standard, and in database brands other than ...