ifx-php-configuration-9

Runtime Configuration

The behaviour of these functions is affected by
settings in php.ini.

Note:

Make sure that the Informix environment variables
INFORMIXDIR and INFORMIXSERVER are available to the PHP ifx driver,
and that the INFORMIX bin directory is in the PATH. Check this by running a script that contains a
call to phpinfo() before you start testing. The
phpinfo() output should list these
environment variables. This is true for both CGI php and Apache
mod_php. You may have to set these environment variables in your
Apache startup script.

The Informix shared libraries should also be
available to the loader (check LD_LIBRARY_PATH or
ld.so.conf/ldconfig).

Note: Some notes on the
use of BLOBs (TEXT and BYTE columns)

BLOBs are normally addressed by BLOB identifiers.
Select queries return a “blob id” for every BYTE and TEXT column.
You can get at the contents with “string_var =
ifx_get_blob($blob_id);” if you choose to get the BLOBs in memory
(with: “ifx_blobinfile(0);”). If you prefer to receive the content
of BLOB columns in a file, use “ifx_blobinfile(1);”, and
“ifx_get_blob($blob_id);” will get you the filename. Use normal
file I/O to get at the blob contents.

For insert/update queries you must create these
“blob id’s” yourself with “ifx_create_blob();”. You then plug the blob
id’s into an array, and replace the blob columns with a question
mark (?) in the query string. For updates/inserts, you are
responsible for setting the blob contents with ifx_update_blob().

The behaviour of BLOB columns can be altered by
configuration variables that also can be set at runtime:

configuration variable: ifx.textasvarchar

configuration variable: ifx.byteasvarchar

runtime functions:

ifx_textasvarchar(0): use blob id’s for select
queries with TEXT columns

ifx_byteasvarchar(0): use blob id’s for select
queries with BYTE columns

ifx_textasvarchar(1): return TEXT columns as if
they were VARCHAR columns, so that you don’t need to use blob id’s
for select queries.

ifx_byteasvarchar(1): return BYTE columns as if
they were VARCHAR columns, so that you don’t need to use blob id’s
for select queries.

configuration variable: ifx.blobinfile

runtime function:

ifx_blobinfile_mode(0): return BYTE columns in
memory, the blob id lets you get at the contents.

ifx_blobinfile_mode(1): return BYTE columns in a
file, the blob id lets you get at the file name.

If you set ifx_text/byteasvarchar to 1, you can use
TEXT and BYTE columns in select queries just like normal (but
rather long) VARCHAR fields. Since all strings are “counted” in
PHP, this remains “binary safe”. It is up to you to handle this
correctly. The returned data can contain anything, you are
responsible for the contents.

If you set ifx_blobinfile to 1, use the file name
returned by ifx_get_blob(..) to get at the blob contents. Note that
in this case YOU ARE RESPONSIBLE FOR DELETING THE TEMPORARY FILES
CREATED BY INFORMIX when fetching the row. Every new row fetched
will create new temporary files for every BYTE column.

The location of the temporary files can be
influenced by the environment variable “blobdir”, default is “.”
(the current directory). Something like: putenv(blobdir=tmpblob”);
will ease the cleaning up of temp files accidentally left behind
(their names all start with “blb”).

Note: Automatically
trimming “char” (SQLCHAR and SQLNCHAR) data

This can be set with the configuration variable

ifx.charasvarchar: if set to 1 trailing spaces will
be automatically trimmed, to save you some “chopping”.

Note:
NULL values

The configuration variable ifx.nullformat (and the
runtime function ifx_nullformat()) when set to
TRUE will return
NULL columns as the string
“NULL“, when set to
FALSE they return the empty string.
This allows you to discriminate between
NULL columns and empty columns.

For further details and definitions of the PHP_INI_* modes, see the
Where a
configuration setting may be set.

Here’s a short explanation of the configuration
directives.

ifx.allow_persistent boolean

Whether to allow persistent Informix
connections.

ifx.max_persistent integer

The maximum number of persistent Informix
connections per process.

ifx.max_links integer

The maximum number of Informix connections per
process, including persistent connections.

ifx.default_host string

The default host to connect to when no host is
specified in ifx_connect() or ifx_pconnect(). Doesn’t apply in safe
mode.

ifx.default_user string

The default user id to use when none is specified
in ifx_connect() or ifx_pconnect(). Doesn’t apply in safe
mode.

ifx.default_password string

The default password to use when none is specified
in ifx_connect() or ifx_pconnect(). Doesn’t apply in safe
mode.

ifx.blobinfile boolean

Set to TRUE if you
want to return blob columns in a file,
FALSE if you want them in memory. You
can override the setting at runtime with ifx_blobinfile_mode().

ifx.textasvarchar boolean

Set to TRUE if you
want to return TEXT columns as normal strings in select statements,
FALSE if you want to use blob id
parameters. You can override the setting at runtime with
ifx_textasvarchar().

ifx.byteasvarchar boolean

Set to TRUE if you
want to return BYTE columns as normal strings in select queries,
FALSE if you want to use blob id
parameters. You can override the setting at runtime with
ifx_textasvarchar().

ifx.charasvarchar boolean

Set to TRUE if you
want to trim trailing spaces from CHAR columns when fetching
them.

ifx.nullformat boolean

Set to TRUE if you
want to return NULL columns as the
literal string “NULL“,
FALSE if you want them returned as
the empty string “”. You can override this setting at runtime with
ifx_nullformat().