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How to do a FULL OUTER JOIN in MySQL?
...MPLE transcribed from this SO question you have:
with two tables t1, t2:
SELECT * FROM t1
LEFT JOIN t2 ON t1.id = t2.id
UNION
SELECT * FROM t1
RIGHT JOIN t2 ON t1.id = t2.id
The query above works for special cases where a FULL OUTER JOIN operation would not produce any duplicate rows. The quer...
Fastest check if row exists in PostgreSQL
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Use the EXISTS key word for TRUE / FALSE return:
select exists(select 1 from contact where id=12)
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What is the difference between std::array and std::vector? When do you use one over other? [duplicat
...inter to an array; e.g., C library routines. (As an aside, std::vector<char> buf(8192); is a great way to allocate a local buffer for calls to read/write or similar without directly invoking new.)
That said, the lack of that extra level of indirection, plus the compile-time constant size, ca...
Get list of all tables in Oracle?
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SELECT owner, table_name
FROM dba_tables
This is assuming that you have access to the DBA_TABLES data dictionary view. If you do not have those privileges but need them, you can request that the DBA explicitly grants you...
How can I remove a trailing newline?
...s the Python equivalent of Perl's chomp function, which removes the last character of a string if it is a newline?
28 Ans...
Is there a combination of “LIKE” and “IN” in SQL?
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An example table:
SQL> create table mytable (something)
2 as
3 select 'blabla' from dual union all
4 select 'notbla' from dual union all
5 select 'ofooof' from dual union all
6 select 'ofofof' from dual union all
7 select 'batzzz' from dual
8 /
Table created.
The origin...
Select first row in each GROUP BY group?
As the title suggests, I'd like to select the first row of each set of rows grouped with a GROUP BY .
17 Answers
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Select count(*) from multiple tables
How can I select count(*) from two different tables (call them tab1 and tab2 ) having as result:
18 Answers
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Convert string to binary in python
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What about converting more-than-one-byte chars, like β, e.g., which seems to me represented by 11001110 10110010 internally?
– Sergey Bushmanov
Mar 25 '17 at 20:18
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Insertion Sort vs. Selection Sort
I am trying to understand the differences between Insertion Sort and Selection Sort.
20 Answers
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