nvarchar

问题 I'm having a UserID field in my table and I need to get that value in my app and whenever I would like to add a new record it should increment by value '1' . So this is how I'm trying to get the last ID enetered from my table. For Example I'm having a value as "A000" and I need to increment that value by '1' so that it should become "A001" and so on..and after 'A999' as pointed out by PinnyM' it should become 'A1000' . I don't want to write any stored procedures or anyother way from database

问题 If there are 2 columns in database, eg. code varchar(3) name nvarchar(50) How to tell hibernate to pass varchar for searching by code? In the hibernate mappings string is mapped to nvarchar and it produces queries like: Select code, name From table where code=N'AAA' (instead of code='AAA') This is very bad as it causes index scan instead of index seek operation (scanning all index nodes instead of directly going to requested one) As code is used in millions of rows as well as in several

问题 If there are 2 columns in database, eg. code varchar(3) name nvarchar(50) How to tell hibernate to pass varchar for searching by code? In the hibernate mappings string is mapped to nvarchar and it produces queries like: Select code, name From table where code=N'AAA' (instead of code='AAA') This is very bad as it causes index scan instead of index seek operation (scanning all index nodes instead of directly going to requested one) As code is used in millions of rows as well as in several

问题 If there are 2 columns in database, eg. code varchar(3) name nvarchar(50) How to tell hibernate to pass varchar for searching by code? In the hibernate mappings string is mapped to nvarchar and it produces queries like: Select code, name From table where code=N'AAA' (instead of code='AAA') This is very bad as it causes index scan instead of index seek operation (scanning all index nodes instead of directly going to requested one) As code is used in millions of rows as well as in several

问题 I am currently trying to convert all columns in all tables of my database from char to nvarchar in SQL server 2012. the query I am trying to run is select cast((select COLUMN_NAME from INFORMATION_SCHEMA.COLUMNS where DATA_TYPE = 'char') as nvarchar(MAX)) Not sure if I should be changing the data type through INFORMATION_SCHEMA.COLUMNS but I found this to be the best way to grab the datatype. the error I am currently getting is: Subquery returned more than 1 value. This is not permitted when

问题 I'm trying to calculate SHA1 hash of a unicode string using T-SQL. The below code works fine with ASCII strings: declare @input varchar(50) set @input = 'some text' print 'SHA1 Hash: ' + UPPER(master.dbo.fn_varbintohexsubstring(0, HashBytes('SHA1', @input), 1, 0)) but it calculates wrong hash when I replace first line of code with declare @input nvarchar(50) . Calculated hash (nvarchar): BBA91B680CE2685E9465DE24967E425CF055B10F Calculated hash by a tool :

问题 I'm trying to calculate SHA1 hash of a unicode string using T-SQL. The below code works fine with ASCII strings: declare @input varchar(50) set @input = 'some text' print 'SHA1 Hash: ' + UPPER(master.dbo.fn_varbintohexsubstring(0, HashBytes('SHA1', @input), 1, 0)) but it calculates wrong hash when I replace first line of code with declare @input nvarchar(50) . Calculated hash (nvarchar): BBA91B680CE2685E9465DE24967E425CF055B10F Calculated hash by a tool :

问题 I'm developing an application which must support several languages. To solve the special characters problem I'm using NVarhcar for my text fields. So my SQL query for a text field is insert into tbl_text(text)values(N'Chci tančit v oblasti') My problem is to put it in SqlCommand, wich is "insert into tbl_text(text)values(N@text)" . It saves "N@text" in the DB table, sure. Do you guys know someway to do it? I'm using C# and SQL 2008. Sorry if it was hard to understand my question. My English

问题 In SQL Server 2008 (TSQL), I've created a stored procedure like this: CREATE PROCEDURE SP_1_10_2 AS declare @mostValuableBook nvarchar(255) SELECT @mostValuableBook = Name FROM books WHERE price = ( SELECT MAX(price) FROM books WHERE izd LIKE '%BHV%' ); return @mostValuableBook GO But, when I'm trying to execute it: declare @x nvarchar(255) EXECUTE @x = SP_1_10_2; SELECT 'The most expensive BHV book:', @x AS 'Name' GO I'm getting an error: Conversion failed when converting the nvarchar value

问题 I want insert all rows of a table into another table, and I also want convert a nvarchar field into bigint , but when I use convert(bigint, col1) SQL Server shows an error: Error converting data type nvarchar to bigint How can I fix this problem? 回答1: You could try to use ISNUMERIC to determine those rows that are indeed numeric: UPDATE dbo.YourTable SET BigIntColumn = CAST(NVarcharColumn AS BIGINT) WHERE ISNUMERIC(NVarcharColumn) = 1 That would convert those rows that can be converted - the