大约有 6,100 项符合查询结果（耗时：0.0139秒） [XML]
What is the advantage of using heredoc in PHP? [closed]
...se them to construct SQL queries:
$sql = <<<SQL
select *
from $tablename
where id in [$order_ids_list]
and product_name = "widgets"
SQL;
To me this has a lower probability of introducing a syntax error than using quotes:
$sql = "
select *
from $tablename
where id in [$order_ids...
What's the difference between ConcurrentHashMap and Collections.synchronizedMap(Map)?
...══════╗
║ Property ║ HashMap ║ Hashtable ║ ConcurrentHashMap ║
╠═══════════════╬═══════════════════╬═══════════════════╩═════...
What type of hash does WordPress use?
...
The WordPress password hasher implements the Portable PHP password hashing framework, which is used in Content Management Systems like WordPress and Drupal.
They used to use MD5 in the older versions, but sadly for me, no more. You can generate hashes using this encrypti...
cscope or ctags why choose one over the other? [closed]
... are right. From the man page: The etags program is used to create a tag table file, in a format understood by emacs(1); the ctags program is used to create a similar table in a format understood by vi(1).
– rmk
Dec 29 '09 at 23:44
...
How to export query result to csv in Oracle SQL Developer?
...take an export to your local system from sql developer.
Path : C:\Source_Table_Extract\des_loan_due_dtls_src_boaf.csv
SPOOL "Path where you want to save the file"
SELECT /*csv*/ * FROM TABLE_NAME;
share
...
Paging with Oracle
...ults were returned slightly quicker the first time I ran the queries on my table (113 million+ rows) for the new method:
New method: 0.013 seconds.
Old method: 0.107 seconds.
However, as @wweicker mentioned, the explain plan looks much worse for the new method:
New method cost: 300,110
Old met...
How to create index on JSON field in Postgres?
...
Found:
CREATE TABLE publishers(id INT, info JSON);
CREATE INDEX ON publishers((info->>'name'));
As stated in the comments, the subtle difference here is ->> instead of ->. The former one returns the value as text, the lat...
What does the git index contain EXACTLY?
...ranch you just switched to.
Git 2.20 (Q4 2018) adds an Index Entry Offset Table (IEOT):
See commit 77ff112, commit 3255089, commit abb4bb8, commit c780b9c, commit 3b1d9e0, commit 371ed0d (10 Oct 2018) by Ben Peart (benpeart).
See commit 252d079 (26 Sep 2018) by Nguyễn Thái Ngọc Duy (pclouds).
...
Check if a given key already exists in a dictionary
...
@Mohan Gulati: You understand that a dictionary is a hashtable of keys mapped to values, right? A hashing algorithm converts the key to an integer and the integer is used to find a location in the hash table that matches. en.wikipedia.org/wiki/Hash_table
– hug...
What is a 'thunk'?
...ayed
computation (similar to a closure)
a feature of some virtual function
table implementations (similar to a
wrapper function)
a mapping of machine data from one
system-specific form to another,
usually for compatibility reasons
I have usually seen it used in the third context.
http://en.wikipe...