如何：echo mysql_query（$ show_tables）到标准输出？

Question

i have this php script that gets run by a cronjob everyday:

mysql_connect("$host", "$username", "$password")or die("Could not connect to the database: " . mysql_error()) ;
mysql_select_db("$db_name") or die("Could not select database: " . mysql_error()) ;

//create backup table with current date concatenated to the table name
$create_table = "set @c=concat('create table    rc_profile_table_backup_',date_format(now(),'%Y_%m_%d'))";
$prepare = "prepare stmt from @c";
$execute = "execute stmt";
$deallocate = "deallocate prepare stmt";

mysql_query($create_table);
mysql_query($prepare);
mysql_query($execute);
mysql_query($deallocate);

echo $sql11 = "insert rc_profile_table_backup_".mktime(date("y"),date("m"),date("d"))."select * from   rc_profile_table"."
";

how can i achieve the insert above? I run this script in a cronjob so it must pick up the the table name with the current date and do the insert. how am i going to know the current date?

thanks

Answer 1

Writing to stdout in PHP

You can use the stream wrapper php://stdout or the predefined STDOUT (which is the prefered way):

fwrite(STDOUT, "My text to write to stdout");

Reference: http://php.net/manual/en/wrappers.php.php

Moving some logic of your code to php

Your php would look something like this:

$tableName = "rc_profile_table_backup_" . date("Y_m_d");
mysql_query("CREATE TABLE `{$tableName}` ..."); // insert your schema here
mysql_query("INSERT INTO `{$tableName}` SELECT * FROM `rc_profile_table`");

Other issues with your code

Don't use unnecessary string inserts:

("$db_name")

can be written as

($db_name)

The whole process of preparing, executing and deallocating should be made with the appropriate mysql classes (mysqli, PDO) and not in your own code. They do all this work for you.