[SOLVED] Quotes

[waiwai933]

Hi everyone. What are the differences between the three types of quotes? (ie. ', ", `) Is there perhaps an online manual for these sort of simple questions?

[corbin]

The main differences:

 

In "", variables are parsed, and in '' they're not.

 

 

`` is not technically a quoting delimiter.  It is used in PHP to execute system commands in most contexts.  Example:

 

echo `dir`;

 

Would list the files in the current directory if permissions allowed that.

 

 

`` is also used to wrap object names in MySQL.  Example:

 

SELECT `col1` FROM `some_table`;

[waiwai933]

I see. That makes much sense. So why do we sometimes use '{$variable}' and other times we use `$variable` in MySQL?

[corbin]

I see. That makes much sense. So why do we sometimes use '{$variable}' and other times we use `$variable` in MySQL?

 

 

Anything wrapped in `` in MySQL is treated as an object.  Object might not actually be the right term there.  What I mean is the name of something.  A table, database, column, stored procedure, whatever.

 

The single quotes are usually used in double quotes:

 

$query = "SELECT * FROM table1 WHERE column1 = '{$var}';";

 

Then, since the $var is in double quotes, it would be parsed.