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Java Constructor Inheritance
...is never null, so this method won't fail
System.out.println(detail.concat(": ").concat(msg));
}
}
// Client code:
Sub s = new Sub("message"); // Calling Super constructor - detail is never initialized!
s.print(); // throws NullPointerException
From this example, you see that you'd need...
What does the exclamation mark do before the function?
... a semi-colon insertion, so it's impossible for this version to be wrongly concatenated with a file that doesn't end with a ;. If you have the () form, it would consider it a function call of whatever was defined in the previous file. Tip of the hat to a co-worker of mine.
– Ju...
Use of .apply() with 'new' operator. Is this possible?
...
small fix : instead of [null,arr] - [null].concat(arr)
– Royi Namir
Mar 11 '14 at 7:57
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show 16 more commen...
How to select rows that have current day's timestamp?
...e the easiest in my opinion:
SELECT * FROM `table` WHERE `timestamp` like concat(CURDATE(),'%');
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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...
Group by month and year in MySQL
... like this
SELECT onDay, id,
sum(pxLow)/count(*),sum(pxLow),count(`*`),
CONCAT(YEAR(onDay),"-",MONTH(onDay)) as sdate
FROM ... where stockParent_id =16120 group by sdate order by onDay
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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 ...
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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Get the new record primary key ID from MySQL insert query?
...T INTO
document (Code, Title, Body)
VALUES (
sha1( concat (convert ( now() , char), ' ', getAutoincrementalNextval ('document') ) ),
'Title',
'Body'
);
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Formatting Numbers by padding with leading zeros in SQL Server
...igits which causes NULL result. The contact function is the answer: SELECT CONCAT(REPLICATE('0',6-LEN(CONVERT(varchar,EmployeeId))) , EmployeeId)
– Mahmoud Moravej
Dec 23 '15 at 5:50
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