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SQL parser library for Java [closed]
... SQL_PARSER.createStatement(query); How can I get the Query body, i.e. the Select, From, Where, etc values?
– quarks
Apr 4 '15 at 17:56
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How to log PostgreSQL queries?
...ement = 'all'
#logging_collector = off to logging_collector = on
Optional: SELECT set_config('log_statement', 'all', true);
sudo /etc/init.d/postgresql restart or sudo service postgresql restart
Fire query in postgresql select 2+2
Find current log in /var/lib/pgsql/9.2/data/pg_log/
The log files t...
“date(): It is not safe to rely on the system's timezone settings…”
...on the production. There is no error. I have installed the apache, php and MySQL manually on window 10. PHP, MySQL and Apache work. But, this project is giving error.
– Hafiz Shehbaz Ali
Dec 29 '15 at 17:18
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What do the following phrases mean in C++: zero-, default- and value-initialization?
...object is set to the value of 0 (zero) converted to T;
— if T is a non-union class type, each nonstatic data member and each base-class subobject is zero-initialized;
— if T is a union type, the object’s first named data member is zero-initialized;
— if T is an array type, each element...
Count the occurrences of DISTINCT values
...
SELECT name,COUNT(*) as count
FROM tablename
GROUP BY name
ORDER BY count DESC;
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How can I compare two lists in python and return matches
... answer is more flexible and readable, since people may need difference or union.
– Shihe Zhang
Nov 1 '17 at 2:31
What...
Count(*) vs Count(1) - SQL Server
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The optimizer recognizes it for what it is: trivial.
The same as EXISTS (SELECT * ... or EXISTS (SELECT 1 ...
Example:
SELECT COUNT(1) FROM dbo.tab800krows
SELECT COUNT(1),FKID FROM dbo.tab800krows GROUP BY FKID
SELECT COUNT(*) FROM dbo.tab800krows
SELECT COUNT(*),FKID FROM dbo.tab800krows GROU...
How is null + true a string?
...solution rules of §7.5.3 are applied to the set of candidate operators to select the best operator with respect to the argument list (x, y), and this operator becomes the result of the overload resolution process. If overload resolution fails to select a single best operator, a binding-time error o...
Updating MySQL primary key
...e, user_interactions u write, user_interactions write;
insert into fixit
select user_2, user_1, type, max(timestamp), count(*) n from user_interactions u
group by user_2, user_1, type
having n > 1;
delete u from user_interactions u, fixit
where fixit.user_2 = u.user_2
and fixit.user_1 = u...
difference between primary key and unique key
...ey, unique key, etc are collectively called as Candidate Key.
However, DBA selected a key from candidate key for searching records is called Primary key.
Difference between Primary Key and Unique key
1. Behavior: Primary Key is used to identify a row (record) in a table, whereas Unique-key is to...