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Showing posts with the label Selecting a Database

SQL SELECT Commands

1. Login in to the mysql client using the login name and password provided by your instructor (if not already logged in). 2. In the photo_album databases, load the /tmp/photo_album.sql.data file into the database. USE photo_album; SOURCE /tmp/photo_album.sql; 3. Perform an aggregate select against each table to count the number of records located in each table. SELECT COUNT(*) FROM customers; SELECT COUNT(*) FROM comments; SELECT COUNT(*) FROM images; SELECT COUNT(*) FROM logins; 4. Using the customers table, list the customers who are active from closest to farthest termination date (term_date). SELECT * FROM customers WHERE active_customer='True' ORDER BY term_date ASC; 5. Using the logins table, list those with active logins and have logged in during the month of April 2007. SELECT * FROM logins WHERE active_login='True' && last_login LIKE '2007-04%'; 6. Using the images table, list the active images names from the most

Retrieving Data,Selecting a Database,Querying MySQL

Retrieving Data The process of retrieving data once a connection has been made to the MySQL server is similar to the process of interacting with the data through the mysql client. The first thing that needs to be addressed is the database that holds the table (which in turn holds the data). Selecting a Database In the mysql client, a database is identified (or selected) by the USE <database> command. In PHP, this is accomplished with a PHP MySQL API function called mysql_select_db(). This function identifies the database that should be used for any subsequent requests to the data, which eliminates the need to qualify every table (or other MySQL resource) called with the database name. There are two ways to use this function: • mysql_select_db($db_name, $link_id) – Using the mysql_select_db function in this fashion ensures that the resource that initiated the connection to the MySQL server would be selected with the $link_id. The variable, that is identified here