The behaviour of these functions is affected by settings in php.ini.
| Name | Default | Changeable | Changelog | 
|---|---|---|---|
| ingres.allow_persistent | "1" | PHP_INI_SYSTEM | Available since ingres 1.0.0 | 
| ingres.array_index_start | "1" | PHP_INI_ALL | Available since ingres 1.4.0. | 
| ingres.auto | "1" | PHP_INI_ALL | Available since ingres 2.0.0. | 
| ingres.blob_segment_length | "4096" | PHP_INI_ALL | Available since ingres 1.2.0. | 
| ingres.cursor_mode | "0" | PHP_INI_ALL | Available since ingres 1.1.0. | 
| ingres.default_database | NULL | PHP_INI_ALL | Available since ingres 1.0.0 | 
| ingres.default_password | NULL | PHP_INI_ALL | Available since ingres 1.0.0 | 
| ingres.default_user | NULL | PHP_INI_ALL | Available since ingres 1.0.0 | 
| ingres.describe | 1 | PHP_INI_ALL | Available since ingres 2.1.0 | 
| ingres.fetch_buffer_size | 100 | PHP_INI_ALL | Available since ingres 2.1.0 | 
| ingres.max_links | "-1" | PHP_INI_SYSTEM | Available since ingres 1.0.0 | 
| ingres.max_persistent | "-1" | PHP_INI_SYSTEM | Available since ingres 1.0.0 | 
| ingres.reuse_connection | "1" | PHP_INI_ALL | Available since ingres 2.0.0 | 
| ingres.scrollable | "1" | PHP_INI_ALL | Available since ingres 2.0.0. | 
| ingres.trace | "0" | PHP_INI_ALL | Available since ingres 2.0.0. | 
| ingres.trace_connect | "0" | PHP_INI_ALL | Available since ingres 1.2.1. | 
| ingres.utf8 | "1" | PHP_INI_ALL | Available since ingres 2.0.0. | 
Here's a short explanation of the configuration directives.
ingres.allow_persistent
     boolean
    Specifies whether to allow persistent connections to Ingres
ingres.array_index_start
     integer
    
      Specifies the start value for an integer key for arrays
      generated by ingres_fetch_row() or 
      ingres_fetch_array(). By default 
      ingres.array_index_start is set to 1. If you wish
      to make the ingres extension behave like other database extensions set
      this configuration option to 0.
     
ingres.auto
     boolean
    Enables or disables autocommit emulation. Ingres cannot have multiple cursors open with autocommit enabled. When enabled, the driver emulates autocommit.
ingres.blob_segment_length
     integer
    Specifies the amount of memory to use when reading BLOB data, in bytes
ingres.cursor_mode
     integer
    
      Specifies the default mode for cursors opened with ingres_prepare(). Valid values
      are INGRES_CURSOR_UPDATE or INGRES_CURSOR_READONLY.
     
ingres.default_database
     string
    Specifies the default database name to use when connecting to the database server if no other name is specified. Does not apply in SQL safe mode.
ingres.default_password
     string
    Specifies the default password to use when connecting to the database server if no other name is specified. Does not apply in SQL safe mode.
ingres.default_user
     string
    Specifies the default user name to use when connecting to the database server if no other name is specified. Does not apply in SQL safe mode.
ingres.describe
     boolean
    Enables the use of DESCRIBE INPUT to determine the expected data types for queries that use parameters. Available with Ingres 9.1.0 and later. When disabled, queries that have parameters passed may need to manually describe the types of those parameters using the types parameter in ingres_query().
Note:
Enabling this feature with ingres_query() will cause additional communications traffic between this extension and the server. To minimize this additional traffic, use ingres_prepare() and ingres_execute().
ingres.fetch_buffer_size
     integer
    Specifies the number of pre-fetch rows that ingres_fetch_array(), ingres_fetch_object() and ingres_fetch_row() will try and fetch in one fetch operation.
ingres.max_links
     integer
    Specifies the maximum number of Ingres sessions allowed per process or thread. The number of sessions should not exceed the total number of connected sessions configured within Ingres.
ingres.max_persistent
     integer
    Specifies the maximum number of persistent Ingres sessions allowed per process or thread. The number of sessions should not exceed the total number of connected sessions configured within Ingres.
ingres.reuse_connection
     boolean
    Reuses an existing active connection if connecting to the same database with the same user name
ingres.scrollable
     boolean
    
     Enables support for scrollable cursors. When fetching CLOB or BLOB data, this
     should be set to FALSE. Available with Ingres 9.2.0 or later.
     
ingres.trace
     boolean
    
      Enables simple tracing using E_NOTICE messages
     
ingres.trace_connect
     boolean
    
      Prints E_NOTICE messages during
      ingres_connect() or ingres_pconnect() calls
     
ingres.utf8
     boolean
    Assumes that strings being passed to National Character column types (NVARCHAR or NCHAR) are using UTF8 encoding and converts them to UTF16 for the server