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Print multiple arguments in Python
...
#Normal string concatenation
print("sum of", a , "and" , b , "is" , c)
#convert variable into str
print("sum of " + str(a) + " and " + str(b) + " is " + str(c))
# if you want to print in tuple way
print("Sum of %s and %s is %s: " %(a,b,c))
#New style string formatting
print("sum of {} and {}...
How important is the order of columns in indexes?
I've heard that you should put columns that will be the most selective at the beginning of the index declaration. Example:
...
How to capitalize the first letter of a String in Java?
...makes sure the rest of the string is lower-case. That's what I needed when converting from ALL_CAPS enum names.
– Ellen Spertus
Nov 13 '15 at 17:40
add a comment
...
Generate GUID in MySQL for existing Data?
...e BEFORE UPDATE on YourTable
FOR EACH ROW
BEGIN
SET new.guid_column := (SELECT UUID());
END
//
Then execute
UPDATE YourTable set guid_column = (SELECT UUID());
And DROP TRIGGER beforeYourTableUpdate;
UPDATE
Another solution that doesn't use triggers, but requires primary key or unique inde...
SQL DROP TABLE foreign key constraint
...your table, you could use this SQL (if you're on SQL Server 2005 and up):
SELECT *
FROM sys.foreign_keys
WHERE referenced_object_id = object_id('Student')
and if there are any, with this statement here, you could create SQL statements to actually drop those FK relations:
SELECT
'ALTER TABL...
C++ deprecated conversion from string constant to 'char*'
...void foo(char* str);
foo("hello");
The problem is that you are trying to convert a string literal (with type const char[]) to char*.
You can convert a const char[] to const char* because the array decays to the pointer, but what you are doing is making a mutable a constant.
This conversion is pr...
Combining “LIKE” and “IN” for SQL Server [duplicate]
...
Effectively, the IN statement creates a series of OR statements... so
SELECT * FROM table WHERE column IN (1, 2, 3)
Is effectively
SELECT * FROM table WHERE column = 1 OR column = 2 OR column = 3
And sadly, that is the route you'll have to take with your LIKE statements
SELECT * FROM tabl...
JOIN queries vs multiple queries
...han several queries? (You run your main query, and then you run many other SELECTs based on the results from your main query)
...
FIND_IN_SET() vs IN()
...
SELECT name
FROM orders,company
WHERE orderID = 1
AND companyID IN (attachedCompanyIDs)
attachedCompanyIDs is a scalar value which is cast into INT (type of companyID).
The cast only returns numbers up to the...
MySQL JOIN the most recent row only?
...
You may want to try the following:
SELECT CONCAT(title, ' ', forename, ' ', surname) AS name
FROM customer c
JOIN (
SELECT MAX(id) max_id, customer_id
FROM customer_data
GROUP BY customer_id
...