CI_DB_driver

Database Driver Class

This is the platform-independent base DB implementation class. This class will not be called directly. Rather, the adapter class for the specific database will extend and instantiate it.

Class name: CI_DB_driver
Namespace:
This is an abstract class

Properties

$dsn

public string $dsn

Data Source Name / Connect string

Visibility: public

$username

public string $username

Username

Visibility: public

$password

public string $password

Password

Visibility: public

$hostname

public string $hostname

Hostname

Visibility: public

$database

public string $database

Database name

Visibility: public

$dbdriver

public string $dbdriver = 'mysqli'

Database driver

Visibility: public

$subdriver

public string $subdriver

Sub-driver

Visibility: public

$dbprefix

public string $dbprefix = ''

Table prefix

Visibility: public

$char_set

public string $char_set = 'utf8'

Character set

Visibility: public

$dbcollat

public string $dbcollat = 'utf8_general_ci'

Collation

Visibility: public

$encrypt

public mixed $encrypt = FALSE

Encryption flag/data

Visibility: public

$swap_pre

public string $swap_pre = ''

Swap Prefix

Visibility: public

$port

public integer $port = ''

Database port

Visibility: public

$pconnect

public boolean $pconnect = FALSE

Persistent connection flag

Visibility: public

$conn_id

public object $conn_id = FALSE

Connection ID

Visibility: public

$result_id

public object $result_id = FALSE

Result ID

Visibility: public

$db_debug

public boolean $db_debug = FALSE

Debug flag

Whether to display error messages.

Visibility: public

$benchmark

public integer $benchmark

Benchmark time

Visibility: public

$query_count

public integer $query_count

Executed queries count

Visibility: public

$bind_marker

public string $bind_marker = '?'

Bind marker

Character used to identify values in a prepared statement.

Visibility: public

$save_queries

public boolean $save_queries = TRUE

Save queries flag

Whether to keep an in-memory history of queries for debugging purposes.

Visibility: public

$queries

public array<mixed,string> $queries = array()

Queries list

Visibility: public

$query_times

public array $query_times = array()

Query times

A list of times that queries took to execute.

Visibility: public

$data_cache

public array $data_cache = array()

Data cache

An internal generic value cache.

Visibility: public

$trans_enabled

public boolean $trans_enabled = TRUE

Transaction enabled flag

Visibility: public

$trans_strict

public boolean $trans_strict = TRUE

Strict transaction mode flag

Visibility: public

$_trans_depth

protected integer $_trans_depth

Transaction depth level

Visibility: protected

$_trans_status

protected boolean $_trans_status = TRUE

Transaction status flag

Used with transactions to determine if a rollback should occur.

Visibility: protected

$_trans_failure

protected boolean $_trans_failure = FALSE

Transaction failure flag

Used with transactions to determine if a transaction has failed.

Visibility: protected

$cache_on

public boolean $cache_on = FALSE

Cache On flag

Visibility: public

$cachedir

public boolean $cachedir = ''

Cache directory path

Visibility: public

$cache_autodel

public boolean $cache_autodel = FALSE

Cache auto-delete flag

Visibility: public

$CACHE

public object $CACHE

DB Cache object

Visibility: public

$_protect_identifiers

protected boolean $_protect_identifiers = TRUE

Protect identifiers flag

Visibility: protected

$_reserved_identifiers

protected array<mixed,string> $_reserved_identifiers = array('*')

List of reserved identifiers

Identifiers that must NOT be escaped.

Visibility: protected

$_escape_char

protected string $_escape_char = '"'

Identifier escape character

Visibility: protected

$_like_escape_str

protected string $_like_escape_str = " ESCAPE '%s' "

ESCAPE statement string

Visibility: protected

$_like_escape_chr

protected string $_like_escape_chr = '!'

ESCAPE character

Visibility: protected

$_random_keyword

protected array $_random_keyword = array('RAND()', 'RAND(%d)')

ORDER BY random keyword

Visibility: protected

$_count_string

protected string $_count_string = 'SELECT COUNT(*) AS '

COUNT string

Visibility: protected

Methods

__construct

void CI_DB_driver::__construct(array $params)

Class constructor

Visibility: public

Arguments

$params array

initialize

boolean CI_DB_driver::initialize()

Initialize Database Settings

Visibility: public

db_connect

mixed CI_DB_driver::db_connect()

DB connect

This is just a dummy method that all drivers will override.

Visibility: public

db_pconnect

mixed CI_DB_driver::db_pconnect()

Persistent database connection

Visibility: public

reconnect

void CI_DB_driver::reconnect()

Reconnect

Keep / reestablish the db connection if no queries have been sent for a length of time exceeding the server's idle timeout.

This is just a dummy method to allow drivers without such functionality to not declare it, while others will override it.

Visibility: public

db_select

boolean CI_DB_driver::db_select()

Select database

This is just a dummy method to allow drivers without such functionality to not declare it, while others will override it.

Visibility: public

db_set_charset

boolean CI_DB_driver::db_set_charset($charset)

Set client character set

Visibility: public

Arguments

$charset mixed

platform

string CI_DB_driver::platform()

The name of the platform in use (mysql, mssql, etc.

..)

Visibility: public

version

string CI_DB_driver::version()

Database version number

Returns a string containing the version of the database being used. Most drivers will override this method.

Visibility: public

_version

string CI_DB_driver::_version()

Version number query string

Visibility: protected

query

mixed CI_DB_driver::query(string $sql, array $binds, boolean $return_object)

Execute the query

Accepts an SQL string as input and returns a result object upon successful execution of a "read" type query. Returns boolean TRUE upon successful execution of a "write" type query. Returns boolean FALSE upon failure, and if the $db_debug variable is set to TRUE will raise an error.

Visibility: public

Arguments

$sql string
$binds array - = FALSE An array of binding data
$return_object boolean - = NULL

load_rdriver

string CI_DB_driver::load_rdriver()

Load the result drivers

Visibility: public

simple_query

mixed CI_DB_driver::simple_query($sql)

Simple Query This is a simplified version of the query() function. Internally we only use it when running transaction commands since they do not require all the features of the main query() function.

Visibility: public

Arguments

$sql mixed

trans_off

void CI_DB_driver::trans_off()

Disable Transactions This permits transactions to be disabled at run-time.

Visibility: public

trans_strict

void CI_DB_driver::trans_strict(boolean $mode)

Enable/disable Transaction Strict Mode When strict mode is enabled, if you are running multiple groups of transactions, if one group fails all groups will be rolled back.

If strict mode is disabled, each group is treated autonomously, meaning a failure of one group will not affect any others

Visibility: public

Arguments

$mode boolean - = TRUE

trans_start

void CI_DB_driver::trans_start(boolean $test_mode)

Start Transaction

Visibility: public

Arguments

$test_mode boolean - = FALSE

trans_complete

boolean CI_DB_driver::trans_complete()

Complete Transaction

Visibility: public

trans_status

boolean CI_DB_driver::trans_status()

Lets you retrieve the transaction flag to determine if it has failed

Visibility: public

compile_binds

string CI_DB_driver::compile_binds($sql, $binds)

Compile Bindings

Visibility: public

Arguments

$sql mixed
$binds mixed

is_write_type

boolean CI_DB_driver::is_write_type($sql)

Determines if a query is a "write" type.

Visibility: public

Arguments

$sql mixed

elapsed_time

string CI_DB_driver::elapsed_time($decimals)

Calculate the aggregate query elapsed time

Visibility: public

Arguments

$decimals mixed

total_queries

integer CI_DB_driver::total_queries()

Returns the total number of queries

Visibility: public

last_query

string CI_DB_driver::last_query()

Returns the last query that was executed

Visibility: public

escape

mixed CI_DB_driver::escape($str)

"Smart" Escape String

Escapes data based on type Sets boolean and null types

Visibility: public

Arguments

$str mixed

escape_str

string CI_DB_driver::escape_str(string|array<mixed,string> $str, boolean $like)

Escape String

Visibility: public

Arguments

$str string|array<mixed,string> - Input string
$like boolean - Whether or not the string will be used in a LIKE condition

escape_like_str

mixed CI_DB_driver::escape_like_str($str)

Escape LIKE String

Calls the individual driver for platform specific escaping for LIKE conditions

Visibility: public

Arguments

$str mixed

_escape_str

string CI_DB_driver::_escape_str($str)

Platform-dependant string escape

Visibility: protected

Arguments

$str mixed

primary

string CI_DB_driver::primary(string $table)

Primary

Retrieves the primary key. It assumes that the row in the first position is the primary key

Visibility: public

Arguments

$table string - Table name

count_all

integer CI_DB_driver::count_all($table)

"Count All" query

Generates a platform-specific query string that counts all records in the specified database

Visibility: public

Arguments

$table mixed

list_tables

array CI_DB_driver::list_tables(string $constrain_by_prefix)

Returns an array of table names

Visibility: public

Arguments

$constrain_by_prefix string - = FALSE

table_exists

boolean CI_DB_driver::table_exists(string $table_name)

Determine if a particular table exists

Visibility: public

Arguments

$table_name string

list_fields

array CI_DB_driver::list_fields(string $table)

Fetch Field Names

Visibility: public

Arguments

$table string - Table name

field_exists

boolean CI_DB_driver::field_exists($field_name, $table_name)

Determine if a particular field exists

Visibility: public

Arguments

$field_name mixed
$table_name mixed

field_data

array CI_DB_driver::field_data(string $table)

Returns an object with field data

Visibility: public

Arguments

$table string - the table name

escape_identifiers

mixed CI_DB_driver::escape_identifiers($item)

Escape the SQL Identifiers

This function escapes column and table names

Visibility: public

Arguments

$item mixed

insert_string

string CI_DB_driver::insert_string($table, $data)

Generate an insert string

Visibility: public

Arguments

$table mixed
$data mixed

_insert

string CI_DB_driver::_insert($table, $keys, $values)

Insert statement

Generates a platform-specific insert string from the supplied data

Visibility: protected

Arguments

$table mixed
$keys mixed
$values mixed

update_string

string CI_DB_driver::update_string($table, $data, $where)

Generate an update string

Visibility: public

Arguments

$table mixed
$data mixed
$where mixed

_update

string CI_DB_driver::_update($table, $values)

Update statement

Generates a platform-specific update string from the supplied data

Visibility: protected

Arguments

$table mixed
$values mixed

_has_operator

boolean CI_DB_driver::_has_operator($str)

Tests whether the string has an SQL operator

Visibility: protected

Arguments

$str mixed

_get_operator

string CI_DB_driver::_get_operator($str)

Returns the SQL string operator

Visibility: protected

Arguments

$str mixed

call_function

mixed CI_DB_driver::call_function(string $function)

Enables a native PHP function to be run, using a platform agnostic wrapper.

Visibility: public

Arguments

$function string - Function name

cache_set_path

void CI_DB_driver::cache_set_path($path)

Set Cache Directory Path

Visibility: public

Arguments

$path mixed

cache_on

boolean CI_DB_driver::cache_on()

Enable Query Caching

Visibility: public

cache_off

boolean CI_DB_driver::cache_off()

Disable Query Caching

Visibility: public

cache_delete

boolean CI_DB_driver::cache_delete(string $segment_one, string $segment_two)

Delete the cache files associated with a particular URI

Visibility: public

Arguments

$segment_one string - = ''
$segment_two string - = ''

cache_delete_all

boolean CI_DB_driver::cache_delete_all()

Delete All cache files

Visibility: public

_cache_init

boolean CI_DB_driver::_cache_init()

Initialize the Cache Class

Visibility: protected

close

void CI_DB_driver::close()

Close DB Connection

Visibility: public

_close

void CI_DB_driver::_close()

Close DB Connection

This method would be overridden by most of the drivers.

Visibility: protected

display_error

string CI_DB_driver::display_error($error, $swap, $native)

Display an error message

Visibility: public

Arguments

$error mixed
$swap mixed
$native mixed

protect_identifiers

string CI_DB_driver::protect_identifiers($item, $prefix_single, $protect_identifiers, $field_exists)

Protect Identifiers

This function is used extensively by the Query Builder class, and by a couple functions in this class. It takes a column or table name (optionally with an alias) and inserts the table prefix onto it. Some logic is necessary in order to deal with column names that include the path. Consider a query like this:

SELECT * FROM hostname.database.table.column AS c FROM hostname.database.table

Or a query with aliasing:

SELECT m.member_id, m.member_name FROM members AS m

Since the column name can include up to four segments (host, DB, table, column) or also have an alias prefix, we need to do a bit of work to figure this out and insert the table prefix (if it exists) in the proper position, and escape only the correct identifiers.

Visibility: public

Arguments

$item mixed
$prefix_single mixed
$protect_identifiers mixed
$field_exists mixed

_reset_select

void CI_DB_driver::_reset_select()

Dummy method that allows Query Builder class to be disabled and keep count_all() working.

Visibility: protected