[Plugin: Contact Form DB] [BUG] In CFDBIntegrationFormidableForms.php

(WP 4.4.2 + Formidable Forms v.2.0.21)
Contact Form DB, v. 2.9.15 have a bug in file CFDBIntegrationFormidableForms.php at line 59

$sql = "SELECT f.name AS 'key', m.meta_value AS 'value' FROM {$wpdb->prefix}frm_item_metas m, wp_frm_fields f WHERE m.field_id = f.id AND m.item_id = %d";

replace with

$sql = "SELECT f.name AS 'key', m.meta_value AS 'value' FROM {$wpdb->prefix}frm_item_metas m, {$wpdb->prefix}frm_fields f WHERE m.field_id = f.id AND m.item_id = %d";

https://wordpress.org/plugins/contact-form-7-to-database-extension/