Merge pull request #22 from greatislander/issues/18

Introduce `wp db prefix` for getting the `$wpdb->prefix` for a site

Author: danielbachhuber

README.md

@@ -16,7 +16,7 @@ This package implements the following commands:
 Create a new database.
 
 ~~~
-wp db create 
+wp db create
 ~~~
 
 Runs `CREATE_DATABASE` SQL statement using `DB_HOST`, `DB_NAME`,
@@ -83,7 +83,7 @@ specified in wp-config.php.
 Check the current status of the database.
 
 ~~~
-wp db check 
+wp db check
 ~~~
 
 Runs `mysqlcheck` utility with `--check` using `DB_HOST`,
@@ -105,7 +105,7 @@ for more details on the `CHECK TABLE` statement.
 Optimize the database.
 
 ~~~
-wp db optimize 
+wp db optimize
 ~~~
 
 Runs `mysqlcheck` utility with `--optimize=true` using `DB_HOST`,
@@ -127,7 +127,7 @@ for more details on the `OPTIMIZE TABLE` statement.
 Repair the database.
 
 ~~~
-wp db repair 
+wp db repair
 ~~~
 
 Runs `mysqlcheck` utility with `--repair=true` using `DB_HOST`,
@@ -451,6 +451,21 @@ The size defaults to a human-readable number.
     $ wp db size --size_format=mb
     6
 
+### wp db prefix
+
+Display the database table prefix.
+
+~~~
+wp db prefix
+~~~
+
+Display the database table prefix, as defined by the database handler's interpretation of the current site.
+
+**EXAMPLES**
+
+    $ wp db prefix
+    wp_
+
 ## Installing
 
 This package is included with WP-CLI itself, no additional installation necessary.

composer.json

@@ -37,6 +37,7 @@
             "db reset",
             "db check",
             "db optimize",
+            "db prefix",
             "db repair",
             "db cli",
             "db query",

features/db-prefix.feature

@@ -0,0 +1,10 @@
+Feature: Display database table prefix
+
+  Scenario: Display database table prefix for a single WordPress install
+    Given a WP install
+
+    When I run `wp db prefix`
+    Then STDOUT should be:
+      """
+      wp_
+      """

src/DB_Command.php

@@ -264,7 +264,7 @@ public function query( $args, $assoc_args ) {
 	 *
 	 * [--tables=<tables>]
 	 * : The comma separated list of specific tables to export. Excluding this parameter will export all tables in the database.
-	 * 
+	 *
 	 * [--exclude_tables=<tables>]
 	 * : The comma separated list of specific tables that should be skipped from exporting. Excluding this parameter will export all tables in the database.
 	 *
@@ -288,7 +288,7 @@ public function query( $args, $assoc_args ) {
 	 *     # Export all tables matching prefix
 	 *     $ wp db export --tables=$(wp db tables --all-tables-with-prefix --format=csv)
 	 *     Success: Exported to 'wordpress_dbase.sql'.
-	 * 
+	 *
 	 *     # Skip certain tables from the exported database
 	 *     $ wp db export --exclude_tables=wp_options,wp_users
 	 *     Success: Exported to 'wordpress_dbase.sql'.
@@ -650,6 +650,24 @@ public function size( $args, $assoc_args ) {
 		}
 	}
 
+	/**
+	 * Display the database table prefix.
+	 *
+	 * Display the database table prefix, as defined by the database handler's interpretation of the current site.
+	 *
+	 * ## EXAMPLES
+	 *
+	 *     $ wp db prefix
+	 *     wp_
+	 */
+	public function prefix() {
+		@WP_CLI::get_runner()->load_wordpress();
+
+		global $wpdb;
+
+		WP_CLI::log( $wpdb->prefix );
+	}
+
 	private static function get_create_query() {
 
 		$create_query = sprintf( 'CREATE DATABASE `%s`', DB_NAME );