nvarchar

问题 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

问题 This question already has answers here : What size do you use for varchar(MAX) in your parameter declaration? (5 answers) Closed 5 years ago . 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

问题 I'm working with a Java web application backed by a Microsoft SQL Server. I have used nvarchar columns and my plan is to support Unicode characters. So in my JDBC layer I have used getNString() method from the result set and it works fine. However just for curiosity I changed all the getNString() methods to normal getString() methods and it also works fine displaying Unicode characters correctly. I found the similar observation from below question as well Should I be using JDBC getNString()

问题 I'm trying to extract a string from my SQL database, but for some reason my parameters are wrong and I'm not sure why. Here is my code: SQLHENV environHandle; SQLHDBC connectHandle; SQLHSTMT statement; SQLCHAR* connectString = "MY_CONNECTION_STRING"; string path; int jobID; SQLINTEGER pathstrlen = SQL_NTS; SQLAllocHandle(SQL_HANDLE_ENV, SQL_NULL_HANDLE, &environHandle); SQLSetEnvAttr(environHandle, SQL_ATTR_ODBC_VERSION, (SQLPOINTER)SQL_OV_ODBC3, SQL_IS_INTEGER); SQLAllocHandle(SQL_HANDLE_DBC

问题 I have table Tbl1( SomeName nvarchar(64) ) Over OLEDB I'm trying to select SELECT 1 FROM Tbl1 WHERE SomeName = ? binding 3 character unicode as parameter causes: DB_E_ERRORSINCOMMAND(0x80040E14L) "The data types nvarchar and ntext are incompatible in the equal to operator" I have already tried following input bindings: 1) ... currentBind.wType = DBTYPE_VARIANT; currentBind.cbMaxLen = 20 // where data points to valid VT_BSTR allocated by SysAllocString ... 2) ... currentBind.wType = DBTYPE

问题 One of my Join key-selectors looks like this: x => x.A + "-" + x.B NHibernate makes "-" an extra parameter. This parameter gets the SQL type nvarchar and so the whole statement gets converted on the SQL Server from varchar to nvarchar . The problem with this is, that SQL Server has a huge problem if the queried column is of type varchar instead of nvarchar . This is because the column is of another type than the parameter and so the index can't be used . I cannot change the type of the column

问题 I am trying to add this name -> NumāTwó into a table in MS sql server along with the accents. But it is only getting inserted as -> NumaTwó (without ā). I tried many encodings but doesn't seem to work. I have given the DDL of the table below. Please help CREATE TABLE [dbo].[test]( [testname] [nvarchar](40) COLLATE SQL_Latin1_General_CP1253_CI_AI NULL ) ON [PRIMARY] ----------- Insert----------- insert into test values ('NumāTwó'); 回答1: use N as Prefix for Unicode character CREATE TABLE [dbo].

问题 I had a question about the Transcat SQL, below is the sql code; DECLARE @main nVARCHAR(max); --there are over 4000 characters to @main set @main = '01234567890123456789...'; Print len(@main) the length of @main is correct, e.g. 4007 however, if I change the code to below: DECLARE @main nVARCHAR(max); --there are over 4000 characters to @main set @main = N'01234567890123456789...'; Print len(@main) the length of @main will always be 4000, it is weird, I don't understand. Another thing is if I

问题 This question already exists : Closed 8 years ago . Possible Duplicate: overstating field size in database design I have a "description" column in one of my tables which as of now I dont know the maximum size of. But I am assuming it should not be greater than 1000 characters. Question: If I make it nvarchar(4000) [just to be safe] will it have any adverse impact on performance ? Thanks. 回答1: No. NVARCHAR(1000) has all the exact characteristics as NVARCHAR(4000) . As a variable length column

问题 I am using Access 2003 as a front end UI for a SQL Server 2008 database. In looking at my SQL Server database design I am wondering if nvarchar was the right choice to use over varchar. I chose nvarchar because I thought it would be useful in case any characters represented by unicode needed to be entered. However, I didn't think about any possible issues with Access 2003 using the uni-code datatype. Are there any issues with Access 2003 working with unicode datatypes within SQL Server (i.e.