why do you have {} around variables in a sql statement?
why do you use {} around variables in following sql statement?
SELECT
FROM users
W开发者_运维技巧HERE username = '{$_POST['user']}'
I presume you are using SQL from within PHP language.
This syntax with {}
is used to interpolate array elements embedded in quoted string.
For example, composing the following string:
"Good morning {$_POST['user']} !"
will compile output with the value of variable (array element) dereferenced, for instance:
"Good morning noname !"
SQL queries in PHP are composed from strings, so this {}
syntax is used fairly often.
Reference: Variable parsing - complex syntax PHP4+
p.s. It's always a good idea to provide as many details as possible in your question.
you can with the double quotes, but not with the single quotes. the question uses single quotes, so i am not so sure it is in PHP. (mabee it was misstyped for the question)
so
if $_POST['user'] = "fred";
"Good morning {$_POST['user']} !"
translates as Good morning fred !
but
'Good morning {$_POST['user']} !'
translates as Good morning {$_POST['user']} !
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