nvarchar

I have a column in my SQL-2005 database that used to be a varchar(max) , but it has been changed to an nvarchar(max) . Now I need to update my hibernate mapping file to reflect the change, and this is what it used to be: <element type="text" column="Value"/> When I try to run the application, the following error appears: org.hibernate.HibernateException: Wrong column type in [Table] for column Value. Found: ntext, expected: text What should I put in the 'type' attribute to correctly map the column as an nvarchar(max) ? I've tried setting the type to ntext , but hibernate didn't know what that

I am wondering if there is any disadvantage on defining a column of type nvarchar(max) instead of giving it a (smaller) maximum size. I read somewhere that if the column value has more than 4?KB the remaining data will be added to an "overflow" area, which is ok. I'm creating a table where most of the time the text will be of a few lines, but I was wondering if there's any advantage in setting a lower limit and then adding a validation to avoid breaking that limit. Is there any restriction on the creation of indexes with nvarchar(max) column, or anything that pays for having to add the

1、char 定长的存储ASCII码字节数据，过去使用这种类型保存数据，但是由于定长势必浪费存储空间；但是效率高 2、varchar 不定长的存储ASCII码字节数据，即使初始化空间为5，如果只存储长度为3的字节，你们也只是占用3个字节的空间；相比char，varchar可以大量节约空间，但是在效率上稍低，原因是长度的判断导致要移位操作，不过这种影响小的可以不用计算，所以在开发中尽量使用varchar； 3、nvarchar 不定长的存储字符数据，这个与varchar的最大区别就是，varchar存储的是字节，而nvarchar存储的字符，也就是说，如果你初始化的空间是5的话，那么意思是申请了5个字符的空间，对于Unicode编码我们知道不同字符所占的字节是不一样的，但是英文只是一个字节就能满足，中文就不一样了，所以，如果你采用nvarchar作为存储英文的话，那就是大量浪费空间。 4、varchar2 varchar2是oracle可变长的数据类型，在SqlServer中称为varchar，他的特点就是可变长，比如定义表的时候采用 FNAME varchar2(20) 意思是FNAME字段最大采用20个 字节 存储，每个字节就是一个8位，也就是 0-127 的ASCII码，实际上这个FNAME的字符串长度就是最大为 20 ，但是不一定为 20；他是不能存储非ASCII码字符的；

This question already has an answer here: What size do you use for varchar(MAX) in your parameter declaration? 4 answers I've got the following code to pull back a DataTable using a stored procedure and inputting a string parameter @JobNumbers, which is dynamically created string of job numbers (and therefore length is unknown): using (SqlConnection connection = new SqlConnection(con)) { SqlCommand cmd = new SqlCommand("dbo.Mystoredprocedure", connection); cmd.CommandType = CommandType.StoredProcedure; cmd.Parameters.Add("@JobNumbers", SqlDbType.VarChar, 4000); cmd.Parameters["@JobNumbers"]

Here is my predicament. Basically, I need a column in a table to hold up an unknown length of characters. But I was curious if in Sql Server performance problems could arise using a VARCHAR(MAX) or NVARCHAR(MAX) in a column, such as: 'This time' I only need to store 3 characters and most of the time I only need to store 10 characters. But there is a small chances that It could be up to a couple thousand characters in that column, or even possibly a million, It is unpredictable. But, I can guarantee that it will not go over the 2GB limit. I was just curious if there are any performance issues,

What are the advantages and disadvantages of using the nvarchar(max) vs. NText data types in SQL Server? I don't need backward compatibility, so it is fine that nvarchar(max) isn't supported in older SQL Server releases. Edit: Apparently the question also applies to TEXT and IMAGE vs. varchar(max) and varbinary(max) , for those searching for those data-types later. SQLMenace The advantages are that you can use functions like LEN and LEFT on nvarchar(max) and you cannot do that against ntext and text . It is also easier to work with nvarchar(max) than text where you had to use WRITETEXT and

We are going to migrate an application to have it support Unicode and have to choose between unicode character set for the whole database, or unicode columns stored in N[VAR]CHAR2. We know that we will no more have the possibility of indexing column contents with Oracle Text if we choose NVARCHAR2, because Oracle Text can only index columns based on the CHAR type. Apart that, is it likely that other major differences arise when harvesting from Oracle possibilities? Also, is it likely that some new features are added in newer versions of Oracle, but only supporting either CHAR columns or NCHAR

Is there a rule when we must use the Unicode types? I have seen that most of the European languages (German, Italian, English, ...) are fine in the same database in VARCHAR columns. I am looking for something like: If you have Chinese --> use NVARCHAR If you have German and Arabic --> use NVARCHAR What about the collation of the server/database? I don't want to use always NVARCHAR like suggested here What are the main performance differences between varchar and nvarchar SQL Server data types? The real reason you want to use NVARCHAR is when you have different languages in the same column, you