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MySQL - UPDATE query based on SELECT Query
...IN product_types USING(product_type_id)
JOIN web_products w
ON sku=CONCAT('L',SUBSTR(product_type_code,3), 'U',unit_index, 'A',activity_index)
I found that that was too complex to incorporate into a SELECT within mysql, so I created a temporary table, and joined that with the update statem...
Difference between null and empty (“”) Java String
... @Zach L : when String s = null+"a"; it gives output nulla but null.concat("a") it gives the null pointer exception. what is the reason in my first case null+"a"; is working.
– Ved Prakash
Sep 14 '19 at 16:23
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How do I dump an object's fields to the console?
...center", "chomp", "chomp!", "chop", "chop!", "class", "clone", "collect", "concat", "count", "crypt", "delete", "delete!", "detect", "display", "downcase", "downcase!", "dump", "dup", "each", "each_byte", "each_line", "each_with_index", "empty?", "entries", "eql?", "equal?", "extend", "find", "find_...
How can I use an http proxy with node.js http.Client?
...(chunk))
res.on('end', () => {
console.log('DONE', Buffer.concat(chunks).toString('utf8'))
})
})
}
}).on('error', (err) => {
console.error('error', err)
}).end()
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Calculate a MD5 hash from a string
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... in which case, I propose return string.Concat( hash.ComputeHash( Encoding.UTF8.GetBytes(observedText) ).Select( x => x.ToString("x2") ) ); instead. It's a little bit shorter, possibly clearer intention, and performs marginally faster (<10% perf. increase).
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How to combine date from one field with time from another field - MS SQL Server
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This saved me! I was converting both to chars and then concating and then back to DATETIME, but then I couldn't index it, because SQL said it was non-deterministic. This apparently IS deterministic!!! THANK !!! YOU !!!
– eidylon
Mar 14 '12 a...
ORA-00979 not a group by expression
...n in scope, but not group by it (assuming these are numbers, otherwise use CONCAT)
SELECT MAX(unique_id_col) AS unique_id_col, COUNT(1) AS cnt
FROM yourTable GROUP BY col_A, (unique_id_col*0 + col_A);
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How can I get the concatenation of two lists in Python without modifying either one? [duplicate]
In Python, the only way I can find to concatenate two lists is list.extend , which modifies the first list. Is there any concatenation function that returns its result without modifying its arguments?
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How do I get a list of all the duplicate items using pandas in python?
...ds so many times. I prefer method #2: groupby on the ID.
>>> pd.concat(g for _, g in df.groupby("ID") if len(g) > 1)
ID ENROLLMENT_DATE TRAINER_MANAGING TRAINER_OPERATOR FIRST_VISIT_DATE
6 11795 3-Jul-12 0649597-White River VT 0649597-White River VT ...
Concatenating two lists - difference between '+=' and extend()
I've seen there are actually two (maybe more) ways to concatenate lists in Python:
One way is to use the extend() method:
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