Summary of ntext field errors in php and mssql_PHP tutorial

php + mssql makes it really painful. The problem with the ntext field type when reading PHP and mssql comes again: when the content of ntext is too long, the reading is incomplete.

I searched online for a long time, and they all said that there was an error when php read ntext, but I didn’t find an error on my page, so I was depressed. Later I found out that PHP can only read content up to 4K by default. It turned out that my content exceeded 4K. Modification methods are as follows

Next:

1. Upgrade php to php5.

Fortunately, mine is already php5.

2. Adjust the parameters of php.ini and change the default maximum readable size of php to 4K.

; Valid range 0 - 2147483647. Default = 4096.
;mssql.textlimit = 4096

; Valid range 0 - 2147483647. Default = 4096.
;mssql.textsize = 20480

Remove the “;” in front of mssql.textlimit and mssql.textsize, and then change the default value to a larger value, such as 20480 (20K)

3. Restart the web server.

I thought that the exciting moment would come. When I ran the php page, the effect was still the same as before, and the field data was not completely read out. Later, I found information that PHP's support for ntext is not very friendly and needs to be converted to text. So I used

Convert(text, content), but it had no effect and almost killed my iis. I've been searching online for a long time but can't find a solution. Just when I was about to give up, a trying concept made me change the database connection method. I put

Changing odbc_connect to mssql_connect actually succeeded.

php link mssql problem ntext cannot be read

You can obviously connect to the database, but you can't read the data. After some searching on Google and Baidu, I finally found out. It turns out that the ntext field returned by PHP when reading mssql is empty. It is recommended that the ntext field be changed to text.

If there is no ntext field in the table, you can use the following code:

The code is as follows

Copy code

代码如下 复制代码 // Connect to MSSQL $link = mssql_connect（‘KALLESPCSQLEXPRESS’， ‘sa’， ‘phpfi’）; if（！$link 　　 ！mssql_select_db（‘php’， $link）） { die（‘Unable to connect or select database！’）; } // Do a simple query， select the version of // MSSQL and print it. $version = mssql_query（‘SELECT @@VERSION’）; $row = mssql_fetch_array（$version）; echo $row［0］; // Clean up mssql_free_result（$version）; ？》 // Connect to MSSQL $link = mssql_connect(‘KALLESPCSQLEXPRESS’, ‘sa’, ‘phpfi’); if(!$link 　　!mssql_select_db(‘php’, $link)) { die(‘Unable to connect or select database!’); } // Do a simple query, select the version of // MSSQL and print it. $version = mssql_query(‘SELECT @@VERSION’); $row = mssql_fetch_array($version); echo $row［0］; // Clean up mssql_free_result($version); ? 》

If there is an ntext field in the table and it is difficult to modify it back to the text field, you can do the following:

1. Modify php.ini

Open php.ini

代码如下	复制代码
select convert（varchar（255），title） as title， convert（text，content） as content from article

Found: ;mssql.textlimit = 4096 changed to mssql.textlimit = 2147483647 Found: ;mssql.textsize = 4096 changed to mssql.textsize = 2147483647 2. You can use modified fields. Since ntext and nvarchar fields in SQL Server use Unicode encoding to store content, PHP will get an error when reading fields with ntext and nvarchar types through mssql extension. If the title field type is nvarchar and the content field type is ntext, then the following SQL statement will report an error: Wrong: select title, content from article Correct:

{This method is not very practical. If the ntext content is too long, the data will be lost after conversion, which means that long articles will be truncated. Moreover, changing ntext to nvarchar(max) in sql2008 will not work}

3. If you are a virtual host, you can use the adodb component to read. If your host does not support it, there is nothing I can do at the moment.

The code is as follows

Copy code

代码如下 复制代码 include（“adodb/adodb.inc.php”）; //包含adodb类库文件 $conn=NewADOConnection（‘odbc_mssql’）; //连接SQL Server数据库 $conn-》Connect（“Driver={SQL Server};Server=localhost;Database=mydb;”，‘username’，‘password’）; include("adodb/adodb.inc.php"); //Include adodb class library file $conn=NewADOConnection(‘odbc_mssql’); //Connect to SQL Server database $conn-》Connect(“Driver={SQL Server};Server=localhost;Database=mydb;”, ‘username’, ‘password’);

{One thing to note when using adodb is that the prerequisite for using adodbPHP to connect to MSSQL is a driver problem. Before 5.2.10, the driver that comes with PHP only supports MSSQL 7.0. If you want to support MSSQL 2000, you need to change the ntwdblib.dll of MSSQL 2000. (2000.80.2039.0) Copy to System32 or PHP directory

5.2.11 only supports MSSQL 2000. If you need to support MSSQL 2005 and 2008, you need to install the driver provided by Microsoft

So if it is a virtual host, there is basically no way

}

? >

Reading the ntext field of mssql returns empty

代码如下	复制代码
// Connect to MSSQL $link = mssql_connect('KALLESPCSQLEXPRESS', 'sa', 'phpfi'); if(!$link 　　 !mssql_select_db('php', $link)) { die('Unable to connect or select database!'); } // Do a simple query, select the version of // MSSQL and print it. $version = mssql_query('SELECT @@VERSION'); $row = mssql_fetch_array($version); echo $row[0]; // Clean up mssql_free_result($version); ?>

During the test, it was clear that I could connect to the database, but I couldn't read the data. After searching for information, I found that the ntext field returned by PHP when reading mssql was empty. It is recommended that the ntext field be changed to text.

If there is no ntext field in the table, you can use the following code:

The code is as follows	Copy code
// Connect to MSSQL $link = mssql_connect('KALLESPCSQLEXPRESS', 'sa', 'phpfi'); if(!$link 　 !mssql_select_db('php', $link)) { die('Unable to connect or select database!'); } // Do a simple query, select the version of // MSSQL and print it. $version = mssql_query('SELECT @@VERSION'); $row = mssql_fetch_array($version); echo $row[0]; // Clean up mssql_free_result($version); ?>

If there is an ntext field in the table and it is difficult to modify it back to the text field, it can be as follows:

1. Modify php.ini

Open php.ini

Found:

;mssql.textlimit = 4096

Change to

代码如下	复制代码
select convert(varchar(255),title) as title, convert(text,content) as content from article

mssql.textlimit = 2147483647 Found: ;mssql.textsize = 4096 Change to mssql.textsize = 2147483647 2. You can use modified fields. Since ntext and nvarchar fields in SQL Server use Unicode encoding to store content, PHP will get an error when reading fields with ntext and nvarchar types through mssql extension. If the title field type is nvarchar and the content field type is ntext, then the following SQL statement will report an error: Wrong: select title,content from article Correct:

3. If you are a virtual host, you can use the adodb component to read. If your host does not support it, there is nothing I can do at the moment.

代码如下	复制代码
include("adodb/adodb.inc.php"); //包含adodb类库文件 $conn=NewADOConnection('odbc_mssql'); //连接SQL Server数据库 $conn->Connect("Driver={SQL Server};Server=localhost;Database=mydb;",'username','password'); ?>