大约有 5,880 项符合查询结果（耗时：0.0278秒） [XML]
JPA and Hibernate - Criteria vs. JPQL or HQL
...ytime you fire a query using criteriaQuery, it creates a new alias for the table name which does not reflect in the last queried cache for any DB. This leads to an overhead of compiling the generated SQL, taking more time to execute.
Regarding fetching strategies [http://www.hibernate.org/315.html]...
How to check if a string is a valid hex color representation?
..., you can prefix number literals to get a number in other radii.
Here's a table for clarification:
╭─────────────┬────────────┬────────┬───────────────────╮
│ Radix │ Charact...
JavaScript: empty array, [ ] evaluates to true in conditional structures. Why is this?
...
there is a handful table showing unexpected situations using == comparator in the link you posted. I commented just to be careful when expecting true or false evaluation.
– m.rufca
Apr 24 '18 at 21:10
...
Is it good practice to use java.lang.String.intern()?
...5x less memory than rolling your own object pool
Be sure to tune -XX:StringTableSize (the default is probably too small; set a Prime number)
share
|
improve this answer
|
fo...
How do I create a URL shortener?
...n auto-generated, unique numerical key (the auto-incremented id of a MySQL table for example).
For this example, I will use 12510 (125 with a base of 10).
Now you have to convert 12510 to X62 (base 62).
12510 = 2×621 + 1×620 = [2,1]
This requires the use of integer division and modulo. A pseudo...
Creating an R dataframe row-by-row
...
data.table seems to be even faster than pre-allocation using data.frames. Testing here: stackoverflow.com/a/11486400/636656
– Ari B. Friedman
Jul 15 '12 at 2:02
...
It is more efficient to use if-return-return or if-else-return?
...most all if-else-return are cases of guard clauses and those are always testable (mock the tested expression) without the else.
– cowbert
Mar 28 '18 at 3:22
...
Check if Python Package is installed
...s:
import subprocess
import sys
reqs = subprocess.check_output([sys.executable, '-m', 'pip', 'freeze'])
installed_packages = [r.decode().split('==')[0] for r in reqs.split()]
The result:
print(installed_packages)
[
"Django",
"six",
"requests",
]
Check if requests is installed:
i...
Which Java Collection should I use?
...resenting a Collection with no duplicates.
HashSet: A Set backed by a Hashtable. Fastest and smallest memory usage, when ordering is unimportant.
LinkedHashSet: A HashSet with the addition of a linked list to associate elements in insertion order. The "next" element is the next-most-recently insert...
How to atomically delete keys matching a pattern using Redis
...
Lua's unpack transforms a table in a "list of independent variables" (other languages call that explode) but the max number is not dependent on the syste memory; it's fixed in lua through the LUAI_MAXSTACK constant. In Lua 5.1 & LuaJIT it's 8000 a...