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Which MySQL data type to use for storing boolean values
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When I do a select from the standard mysql command line client bit fields shows up completely blank. Because of this I prefer TINYINT(1).
– User
Nov 2 '12 at 0:53
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Can I concatenate multiple MySQL rows into one field?
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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 ...
SQL SELECT WHERE field contains words
I need a select which would return results like this:
15 Answers
15
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Is there any boolean type in Oracle databases?
...l (boolc char(1), booln number(1)); insert into testbool values ('Y', 1 ); select dump(boolc), dump(booln) from testbool; That CHAR is stored: Typ=96 Len=1: 89 and that NUMBER: Typ=2 Len=2: 193,2 At least in 12c, NUMBER(1) can use 2 bytes...
– phil_w
Apr 19 '1...
%Like% Query in spring JpaRepository
...hars as well as a space char following like in your query, as in
@Query("Select c from Registration c where c.place like %:place%").
Cf. http://docs.spring.io/spring-data/jpa/docs/current/reference/html.
You may want to get rid of the @Queryannotation alltogether, as it seems to resemble the st...
Linux C/C++程序常用的调试手段及异常排查总结 - C/C++ - 清泛网 - 专注C/C++及内核技术
...、换行、注释等，可以在经常使用的ide上安装相关格式化插件）
是否涉及动态资源
是否有申请动态内存，文件描述符等，执行完是否有正确释放？指针等操作是否规范？
性能如何
是否有一些执行耗时的操作，I/O，网...
html select option separator
How do you make a separator in a select tag?
14 Answers
14
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How to achieve function overloading in C?
...neric gets the overall type of the expression and then "switches" on it to select the end result expression in the list for its type:
_Generic(1, float: 2.0,
char *: "2",
int: 2,
default: get_two_object());
The above expression evaluates to 2 - the type of the ...
What is the C# equivalent of NaN or IsNumeric?
...eference to the Visual Basic Library by right clicking on your project and selecting "Add Reference":
Then import it in your class as shown below:
using Microsoft.VisualBasic;
Next use it wherever you want as shown below:
if (!Information.IsNumeric(softwareVersion))
{
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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...