| 字段名称 | 介绍 |
|---|---|
| dsn | DSN 连接字符串（该字符串包含了所有的数据库配置信息） |
| hostname | 数据库的主机名，通常位于本机，可以表示为 “localhost” |
| username | 需要连接到数据库的用户名 |
| password | 登陆数据库的密码 |
| database | 需要连接的数据库名 |
| dbdriver | 数据库类型，必须为小写字母 |
| dbprefix | 当使用查询构造器查询时，可以选择性的为表加个前缀，它允许在一个数据库上安装多个 CodeIgniter 程序 |
| pconnect | 是否使用持续连接 |
| db_debug | 是否显示数据库错误信息 |
| cache_on | 是否开启数据库查询缓存 |
| cachedir | 数据库查询缓存目录所在的服务器绝对路径 |
| char_set | 与数据库通信时所使用的字符集 |
| dbcollat | 与数据库通信时所使用的字符规则,注意：只使用于’mysql’和’mysqli’数据库驱动 |
| swap_pre | 替换默认的 dbprefix 表前缀，该项设置对于分布式应用是非常有用的，你可以在查询中使用由最终用户定制的表前缀 |
| encrypt | 是否使用加密连接 |
| compress | 是否使用客户端压缩协议（只用于MySQL） |
| stricton | 是否强制使用 “Strict Mode” 连接, 在开发程序时，使用 strict SQL 是一个好习惯 |
| failover | 当主数据库由于某些原因无法连接时，你还可以配置故障转移（failover） |
| save_queries | 是否“保存”所有已执行的查询 |
/*
| ['dsn'] The full DSN string describe a connection to the database.
| ['hostname'] The hostname of your database server.
| ['username'] The username used to connect to the database
| ['password'] The password used to connect to the database
| ['database'] The name of the database you want to connect to
| ['dbdriver'] The database driver. e.g.: mysqli.
| Currently supported:
| cubrid, ibase, mssql, mysql, mysqli, oci8,
| odbc, pdo, postgre, sqlite, sqlite3, sqlsrv
| ['dbprefix'] You can add an optional prefix, which will be added
| to the table name when using the Query Builder class
| ['pconnect'] TRUE/FALSE - Whether to use a persistent connection
| ['db_debug'] TRUE/FALSE - Whether database errors should be displayed.
| ['cache_on'] TRUE/FALSE - Enables/disables query caching
| ['cachedir'] The path to the folder where cache files should be stored
| ['char_set'] The character set used in communicating with the database
| ['dbcollat'] The character collation used in communicating with the database
| NOTE: For MySQL and MySQLi databases, this setting is only used
| as a backup if your server is running PHP < 5.2.3 or MySQL < 5.0.7
| (and in table creation queries made with DB Forge).
| There is an incompatibility in PHP with mysql_real_escape_string() which
| can make your site vulnerable to SQL injection if you are using a
| multi-byte character set and are running versions lower than these.
| Sites using Latin-1 or UTF-8 database character set and collation are unaffected.
| ['swap_pre'] A default table prefix that should be swapped with the dbprefix
| ['encrypt'] Whether or not to use an encrypted connection.
|
| 'mysql' (deprecated), 'sqlsrv' and 'pdo/sqlsrv' drivers accept TRUE/FALSE
| 'mysqli' and 'pdo/mysql' drivers accept an array with the following options:
|
| 'ssl_key' - Path to the private key file
| 'ssl_cert' - Path to the public key certificate file
| 'ssl_ca' - Path to the certificate authority file
| 'ssl_capath' - Path to a directory containing trusted CA certificates in PEM format
| 'ssl_cipher' - List of *allowed* ciphers to be used for the encryption, separated by colons (':')
| 'ssl_verify' - TRUE/FALSE; Whether verify the server certificate or not
|
| ['compress'] Whether or not to use client compression (MySQL only)
| ['stricton'] TRUE/FALSE - forces 'Strict Mode' connections
| - good for ensuring strict SQL while developing
| ['ssl_options'] Used to set various SSL options that can be used when making SSL connections.
| ['failover'] array - A array with 0 or more data for connections if the main should fail.
| ['save_queries'] TRUE/FALSE - Whether to "save" all executed queries.
*/