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Generating a random password in php
...keyspace A string of all possible characters
* to select from
* @return string
*/
function random_str(
$length,
$keyspace = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
) {
$str = '';
$max = mb_strlen($keyspace, '8bit') - 1;
if ($max...
How well is Unicode supported in C++11?
...port is quite good, though: it supports detecting endianess from a BOM, or selecting it explicitly in code. It also supports producing output with and without a BOM.
There are some more interesting conversion possibilities absent. There is no way to deserialize from an UTF-16 byte stream or string ...
SQL NVARCHAR and VARCHAR Limits
... large (unavoidable) dynamic SQL query. Due to the number of fields in the selection criteria the string containing the dynamic SQL is growing over 4000 chars. Now, I understand that there is a 4000 max set for NVARCHAR(MAX) , but looking at the executed SQL in Server Profiler for the statement
...
Generate random password string with requirements in javascript
...ough bits to "fill up" the full decimal space, the last digit will only be selected from a certain set of values. For example, on my computer, the last digit is only ever "i", "r", and "9". Use this instead: Math.random().toString(36).substr(2, 8)
– Joel
Jan 19...
What is the maximum length of a table name in Oracle?
...ith standard SQL you can also determine the lengths by querying the table: select * from all_tab_columns where table_name = 'ALL_TAB_COLUMNS';
– JustinKSU
Mar 11 '16 at 23:18
1
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Why does Oracle 9i treat an empty string as NULL?
...
@sehe the confusing bit for me is select 1 from dual where ('' is null)
– matt freake
Aug 22 '13 at 15:58
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How can I find non-ASCII characters in MySQL?
...ng as "ASCII", but I would suggest trying a variant of a query like this:
SELECT * FROM tableName WHERE columnToCheck NOT REGEXP '[A-Za-z0-9]';
That query will return all rows where columnToCheck contains any non-alphanumeric characters. If you have other characters that are acceptable, add them ...
Can I concatenate multiple MySQL rows into one field?
...
You can use GROUP_CONCAT:
SELECT person_id, GROUP_CONCAT(hobbies SEPARATOR ', ')
FROM peoples_hobbies
GROUP BY person_id;
As Ludwig stated in his comment, you can add the DISTINCT operator to avoid duplicates:
SELECT person_id, GROUP_CONCAT(DISTINCT ...
What's a quick way to comment/uncomment lines in Vim?
...
For those tasks I use most of the time block selection.
Put your cursor on the first # character, press CtrlV (or CtrlQ for gVim), and go down until the last commented line and press x, that will delete all the # characters vertically.
For commenting a block of text i...
How do you count the number of occurrences of a certain substring in a SQL varchar?
...mparing the lengths
Declare @string varchar(1000)
Set @string = 'a,b,c,d'
select len(@string) - len(replace(@string, ',', ''))
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