大约有 6,200 项符合查询结果（耗时：0.0202秒） [XML]
IN vs OR in the SQL WHERE Clause
...tion Plan.
I tried it with Oracle, and it was exactly the same.
CREATE TABLE performance_test AS ( SELECT * FROM dba_objects );
SELECT * FROM performance_test
WHERE object_name IN ('DBMS_STANDARD', 'DBMS_REGISTRY', 'DBMS_LOB' );
Even though the query uses IN, the Execution Plan says that it u...
PDO's query vs execute
... execution. Which means you can do:
$sth = $db->prepare("SELECT * FROM table WHERE foo = ?");
$sth->execute(array(1));
$results = $sth->fetchAll(PDO::FETCH_ASSOC);
$sth->execute(array(2));
$results = $sth->fetchAll(PDO::FETCH_ASSOC);
They generally will give you a performance impr...
Where can I find a list of scopes for Google's OAuth 2.0 API? [closed]
...
Google's oauth docs display a table that lists all of the available scopes.
https://developers.google.com/+/api/oauth#scopes-table
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Java: parse int value from a char
...ou take '2' - '0' you really just get 50 - 48 = 2. Have a look at an ASCII table in order to understand this principle better. Also, 'x' means get the ascii value of the character in Java.
– Kevin Van Ryckegem
May 13 '17 at 13:16
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Get ID of last inserted document in a mongoDB w/ Java driver
...
This is insert operation:
DBCollection table1 = db.getCollection("Collection name");
BasicDBObject document = new BasicDBObject();
document.put("_id",value);
document.put("Name", name);
table1.insert(document);
After insert u get last inserted id:
DBColle...
SQL order string as number
... cast your column value to an integer explicitly with
select col from yourtable
order by cast(col as unsigned)
or implicitly for instance with a mathematical operation which forces a conversion to number
select col from yourtable
order by col + 0
BTW MySQL converts strings from left to right....
List all environment variables from the command line
...ted by user797717 to avoid output truncation:
Get-ChildItem Env: | Format-Table -Wrap -AutoSize
Source: Creating and Modifying Environment Variables (Windows PowerShell Tip of the Week)
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How to detect reliably Mac OS X, iOS, Linux, Windows in C preprocessor? [duplicate]
... a corollary answer: the people on [this site] have taken the time to make tables of macros defined for every OS/compiler pair.
For example, you can see that _WIN32 is NOT defined on Windows with Cygwin (POSIX), while it IS defined for compilation on Windows, Cygwin (non-POSIX), and MinGW with ever...
Convert timestamp to date in MySQL query
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Convert timestamp to date in MYSQL
Make the table with an integer timestamp:
mysql> create table foo(id INT, mytimestamp INT(11));
Query OK, 0 rows affected (0.02 sec)
Insert some values
mysql> insert into foo values(1, 1381262848);
Query OK, 1 row affected (...
Entity Framework 4 vs NHibernate [closed]
...hat EF4 has more flexible inheritance mapping. For instance, you can use 2 tables (TPT) as base class + level 1 class and add discriminator to level 1 table, allowing spliting to level 2 classes. In NH, discriminator can only be defined on base class.
– Danny Varod
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