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Importance of varchar length in MySQL table
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Anytime your select query uses a temporary table (group and order by operations, among other things) it will convert varchar(200) to a char(200) and performance will suffer.
– Jamie
Feb 7 '13 at 20:1...
Binary Data in MySQL [closed]
... mysql_connect("localhost", "root", "password");
mysql_select_db("binary_data");
$data = mysql_real_escape_string(fread(fopen($form_data, "r"), filesize($form_data)));
$result = mysql_query("INSERT INTO binary_data (description, bin_data, filenam...
CentOS+Nginx+PHP+MySQL详细配置(图解) - PHP - 清泛IT论坛，有思想、有深度
...PHP-FPM说白了是一个管理FastCGI的一个管理器，它作为PHP的插件纯在，在安装PHP要想使用PHP-FPM时就需要把PHP-FPM以补丁的形式安装到PHP中，而且PHP要与PHP-FPM版本一致，这是必须的，切记！
首先我们把PHP和PHP-FPM...
How To Test if Type is Primitive
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where t.IsValueType
select typeof (Nullable<>).MakeGenericType(t);
List = types.Concat(nullTypes).ToArray();
}
public static bool Test(Type type)
{
if (List.Any(x => x.IsAssignableFrom(type))...
Auto increment primary key in SQL Server Management Studio 2012
...h non-zero scale) and ofc, the identity spec should be compatible with the selected data type.
– Pred
Feb 4 '15 at 14:36
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Storing Data in MySQL as JSON
... statement, including WHERE, ORDER BY, and GROUP BY clauses. This includes SELECT, UPDATE, DELETE, CREATE TABLE, and other SQL statements. The left hand side must be a JSON column identifier (and not an alias). The right hand side is a quoted JSON path expression which is evaluated against the JSON ...
How to display a dynamically allocated array in the Visual Studio debugger?
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For beginners: If you select "a" variable, right click and add to watch list (inspect), if you open de debugger view in the list of watched values (I can't find the name of the window right now), you can double click "a" and rename it "a,X" where ...
INSERT with SELECT
I have a query that inserts using a select:
8 Answers
8
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How to get a float result by dividing two integer values using T-SQL?
...s or parameters which are integers, you can cast them to be floats first:
SELECT CAST(1 AS float) / CAST(3 AS float)
or
SELECT CAST(MyIntField1 AS float) / CAST(MyIntField2 AS float)
share
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i...
How to run SQL script in MySQL?
... If the purpose of writing to file is taking data dump, I guess SELECT ... INTO OUTFILE /path/to/file.csv is more efficient way. See options and syntax here - dev.mysql.com/doc/refman/5.7/en/select-into.html
– Anis
Feb 21 '18 at 6:43
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