Blank (not null) columns retrieved from SQL Server 2014 were returning a single space.
Setting "tds version = 7.0" in /etc/freetds/freetds.conf fixed the issue.
(PECL PDO_DBLIB >= 0.9.0)
PDO_DBLIB DSN — Connecting to Microsoft SQL Server and Sybase databases
The PDO_DBLIB Data Source Name (DSN) is composed of the following elements:
The DSN prefix is sybase:
if PDO_DBLIB was
linked against the Sybase ct-lib libraries,
mssql:
if PDO_DBLIB was linked against the
Microsoft SQL Server libraries, or dblib:
if
PDO_DBLIB was linked against the FreeTDS libraries.
host
The hostname on which the database server resides. Defaults to 127.0.0.1.
dbname
The name of the database.
charset
The client character set.
appname
The application name (used in sysprocesses). Defaults to "PHP Generic DB-lib" or "PHP freetds".
secure
Currently unused.
Example #1 PDO_DBLIB DSN examples
The following examples show a PDO_DBLIB DSN for connecting to Microsoft SQL Server and Sybase databases:
mssql:host=localhost;dbname=testdb sybase:host=localhost;dbname=testdb dblib:host=localhost;dbname=testdb
Blank (not null) columns retrieved from SQL Server 2014 were returning a single space.
Setting "tds version = 7.0" in /etc/freetds/freetds.conf fixed the issue.
Instead of specifying tds version and client charset in freetds.conf, you may pass it as a parameter.
<?php $dsn = 'dblib:version=7.0;CHARSET=gb2312;host=domain.example.com;dbname=example;'; ?>
If you're using FreeTDS driver and you want to use "charset" parameter then you may have to edit freetds.conf (e.g. /etc/freetds/freetds.conf) and force connection using at least version 7.0 of the protocol.
tds version = 7.0
Charset parameter accepts all encodings supported by iconv (execute iconv --list to show all encodings).
Be careful if you are using dblib with prepared statement, as it will crash if first execution didn't return anything.
referring to https://bugs.php.net/bug.php?id=40639
on Linux ppc64 / PHP 5.1.2 / freetds-0.64 works well this way:
<?php
// ...
$dbh = new PDO("dblib:host=$hostdb;dbname=$dbname", $usr, $psw);
// ...
?>
when you connect to non standart 1433 port
for win32 use DSN like 'mssql:host=hostname,port;dbname=database'
for FreeTDS and DB-Lib use DSN like 'mssql:host=hostname:port;dbname=database'