大约有 48,000 项符合查询结果（耗时：0.0203秒） [XML]
How do I find duplicate values in a table in Oracle?
...= oed.deptid )
group by oed.empid having count(oed.empid) > 1 order by count(oed.empid);
and if such table has primary key then use primary key instead of rowid, e.g id is pk then
select oed.empid, count(oed.empid)
from emp_dept oed
where exists ( select *
from emp...
Difference between FetchType LAZY and EAGER in Java Persistence API?
...
@ADTC In order for lazy loading to work, the JDBC session must still be open when the target entities want to be loaded into the memory by invoking the getter method (e.g. getStudents()), but sometimes this is not possible, because by...
static const vs #define
...#define simply replaces the text. Because doing this can seriously mess up order of operations, I would recommend using a constant variable instead.
share
|
improve this answer
|
...
How to enable MySQL Query Log?
...
It's ok to save those settings in conf file in order to be applied every time that MySQL is started, but you don't need to restart MySQL to apply this configuration. You can set it using 'SET global' like others said.
– Angel
Apr 8 '...
What XML parser should I use in C++? [closed]
... requires you to do a lot of explicit memory allocation of string names in order to build its DOM. It does provide a kind of string buffer, but that still requires a lot of explicit work on your end. It's certainly functional, but it's a pain to use.
It uses the MIT licence. It is a header-only libr...
Difference between Eclipse Europa, Helios, Galileo
...d how the names of the last three and the next release are in alphabetical order (Galileo, Helios, Indigo, Juno)? This is probably how they will go in the future, in the same way that Ubuntu release codenames increase alphabetically (note Indigo is not a moon of Jupiter!).
...
MySQL indexes - what are the best practices?
...tant to understand what's going on.
Broadly speaking, an index imposes an ordering on the rows of a table.
For simplicity's sake, imagine a table is just a big CSV file. Whenever a row is inserted, it's inserted at the end. So the "natural" ordering of the table is just the order in which rows...
Understanding ibeacon distancing
...info form accelerometer to detect whether user is moving (and how fast) in order to reset the previous distribution distance values because they have certainly changed.
share
|
improve this answer
...
Implications of foldr vs. foldl (or foldl')
... To avoid confusion, note that the parentheses do not show the actual order of evaluation. Since Haskell is lazy the outermost expressions will be evaluated first.
– Lii
Oct 29 '13 at 16:29
...
Dump a mysql database to a plaintext (CSV) backup from the command line
...
In MySQL itself, you can specify CSV output like:
SELECT order_id,product_name,qty
FROM orders
INTO OUTFILE '/tmp/orders.csv'
FIELDS TERMINATED BY ','
ENCLOSED BY '"'
LINES TERMINATED BY '\n'
From http://www.tech-recipes.com/rx/1475/save-mysql-query-results-into-a-text-or-csv-fil...