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Why can't I use switch statement on a String?
...nse, they are used as an index (after subtracting the lowest value) into a table of instruction pointers—the tableswitch instruction.
If the constants are sparse, a binary search for the correct case is performed—the lookupswitch instruction.
In de-sugaring a switch on String objects, both i...
When is CRC more appropriate to use than MD5/SHA1?
...
I found a study that shows how inappropriate CRC hashes are for hash tables. It also explains the actual characteristics of the algorithm. The study also includes evaluation of other hash algorithms and is a good reference to keep.
The relevant conclusion on CRC for hashes:
CRC32 was neve...
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...
Vertically aligning CSS :before and :after content [duplicate]
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You can also use tables to accomplish this, like:
.pdf {
display: table;
}
.pdf:before {
display: table-cell;
vertical-align: middle;
}
Here is an example: https://jsfiddle.net/ar9fadd0/2/
EDIT:
You can also use flex to accomplish t...
CSS to stop text wrapping under image
...:
float: left / right
overflow: hidden / auto / scroll
display: table-cell and any table-related values / inline-block
position: absolute / fixed
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How to list active / open connections in Oracle?
Is there any hidden table, system variable or something to show active connections in a given moment?
9 Answers
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How to use Oracle ORDER BY and ROWNUM correctly?
...ory, in Oracle, you need to limit the results manually when you have large tables and/or tables with same column names (and you don't want to explicit type them all out and rename them all). Easy solution is to figure out your breakpoint and limit that in your query. Or you could also do this in the...
CodeIgniter activerecord, retrieve last insert id?
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for Specific table you cannot use $this->db->insert_id() . even the last insert happened long ago it can be fetched like this. may be wrong. but working well for me
$this->db->select_max('{primary key}');
$result= $...
How to convert local time string to UTC?
... platform. You could use tzlocal.get_localzone() to provide tzdata in a portable way. (2) fromtimestamp(t, tz) may fail for non-pytz timezones. (3) datetime(*struct_time[:6]) you are missing *. (4) timegm(), utctimetuple(), struct_time -based solutions drop fractions of a second. You could use an e...
win7 安装项目管理工具redmine2.5.1 - 开源 & Github - 清泛网 - 专注C/C++及内核技术
...服务
b. 然后在my.ini文件中的[mysqld]下面一行添加skip_grant_tables (加上这句话,my.ini一般在mysql的data目录)
c. 再次输入mysql -u root -p ,这时cmd将切换成mysql模式
输入: UPDATE user SET Password=PASSWORD('newpassword') where USER='root';(注意...