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Combined area of overlapping circles
...d four circles (midpoints and radius) and had to calculate the area of the union of these circles.
14 Answers
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Enable binary mode while restoring a Database from an SQL dump
I am extremely new to MySQL and am running it on Windows. I am trying to restore a Database from a dumpfile in MySQL, but I get the following error:
...
PostgreSQL: Show tables in PostgreSQL
What's the equivalent to show tables (from MySQL) in PostgreSQL?
24 Answers
24
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Difference between 'struct' and 'typedef struct' in C++?
...different categories of identifiers, including tag identifiers (for struct/union/enum) and ordinary identifiers (for typedef and other identifiers).
If you just said:
struct Foo { ... };
Foo x;
you would get a compiler error, because Foo is only defined in the tag namespace.
You'd have to dec...
Pandas groupby: How to get a union of strings
I have a dataframe like this:
8 Answers
8
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How to truncate a foreign key constrained table?
...
As per mysql documentation, TRUNCATE cannot be used on tables with foreign key relationships. There is no complete alternative AFAIK.
Dropping the contraint still does not invoke the ON DELETE and ON UPDATE.
The only solution I can...
How to find the php.ini file used by the command line?
I need to enable pdo_mysql in my EasyPhp environment, so I went to php.ini file and uncommented the following line:
14 Answ...
Can you create nested WITH clauses for Common Table Expressions?
...:
WITH y
AS
(
SELECT x, y, z
FROM MyTable
WHERE [base_condition]
UNION ALL
SELECT x, y, z
FROM MyTable M
INNER JOIN y ON M.[some_other_condition] = y.[some_other_condition]
)
SELECT *
FROM y
You may not need this functionality. I've done the following just to organize my queries ...
Keeping it simple and how to do multiple CTE in a query
...cte2 AS
(
SELECT 2 AS id
)
SELECT *
FROM cte1
UNION ALL
SELECT *
FROM cte2
UNION ALL
SELECT *
FROM cte1
Note, however, that SQL Server may reevaluate the CTE each time it is accessed, so if you are using values like RAND(), NEWID() etc., they may change between...
How do I see all foreign keys to a table or column?
In MySQL, how do I get a list of all foreign key constraints pointing to a particular table? a particular column? This is the same thing as this Oracle question , but for MySQL.
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