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For loop example in MySQL
...+1;
end while;
commit;
end #
delimiter ;
call load_foo_test_data();
select * from foo order by id;
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Possible to do a MySQL foreign key to one of two possible tables?
...ecific type of filter is easy if you know which type you want to join to:
SELECT * FROM Products
INNER JOIN FiltersType2 USING (product_id)
If you want the filter type to be dynamic, you must write application code to construct the SQL query. SQL requires that the table be specified and fixed at ...
Search code inside a Github project
...valid search query. Try quoting it." is gone when using the default search selector "Everything":)
(I suppose we can all than Tim Pease, which had in one of his objectives "hacking on improved search experiences for all GitHub properties", and I did mention this Stack Overflow question at the time ...
创建增量同步Oracle物化视图问题 - 数据库(内核) - 清泛网 - 专注C/C++及内核技术
..._tablename refresh fast on demand start with sysdate next sysdate+1/288 as select * from T_tablename@dblink_name;”。
现在，数据库A上此表的主键约束因主键字段值重复而被disable了，在第三个数据库C上新建这个物化视图却失败，说：“ORA-12014: 表 'T_MV_TE...
How can I get useful error messages in PHP?
...t to make these changes at the .ini file level. Turning on error reporting from within a script is useless, as it won't help with syntax errors or other fatal errors that kill the compile phase. The script gets killed long before it begins executing and reaches the reporting overrides.
...
How to get the date from jQuery UI datepicker
...tepicker_id').datepicker('getDate');
if (jsDate !== null) { // if any date selected in datepicker
jsDate instanceof Date; // -> true
jsDate.getDate();
jsDate.getMonth();
jsDate.getFullYear();
}
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data.table vs dplyr: can one do something well the other can't or does poorly?
... ## data.table syntax
left_join(DT2, DT1) ## dplyr syntax
# 2. select columns while join
DT1[DT2, .(z, i.mul)]
left_join(select(DT2, x, y, mul), select(DT1, x, y, z))
# 3. aggregate while join
DT1[DT2, .(sum(z) * i.mul), by = .EACHI]
DF1 %>% group_by(x, y) %>% summarise(z = su...
How to use Servlets and Ajax?
...and execute the following function with Ajax response JSON...
var $select = $("#someselect"); // Locate HTML DOM element with ID "someselect".
$select.find("option").remove(); // Find all child elements with tag name "option" and rem...
How do I force detach Screen from another SSH session?
...
Reattach without ejecting others: screen -x
Get list of displays: ^A *, select the one to disconnect, press d
Explained answer
Background: When I was looking for the solution with same problem description, I have always landed on this answer. I would like to provide more sensible solution. (...
What do people think of the fossil DVCS? [closed]
... extremely robust, even on large projects. I wouldn't expect anything else from the guys who wrote sqlite. No crashes, no corruption, no funny business.
4) I'm actually very, very happy with performance. Not as fast as git on huge trees, but not much slower either. I make up any lost time by not ha...