select_avg([$select = ''[, $alias = '']])

elapsed_time([$decimals = 6])

database_exists($database_name)

table_exists($table_name)

escape_str($str[, $like = FALSE])

set_update_batch($key[, $value = ''[, $escape = NULL]])

CodeIgniter has a config file that lets you store your database connection values (username, password, database name, etc.). The config file is located at application/config/database

initialize()

repair_table($table_name)

truncate([$table = ''])