Since SQL Server 2005, import and export wizards are different from SQL Server 2000. To import a text file (.txt,. Csv) into the database table. The new version of the Import and Export Wizard takes the first 200 rows of data of the text file by default (the number of rows can be changed in the selection of flat data source-advanced-suggested type) to determine the (minimum) data type of each field, and then converts the data type of the text file field into the data type of the corresponding field in the data table when importing. This may cause truncation and type conversion errors.

The solution is to manually select the data source (text file), and then after selecting the data source (text), specify the DataType and OutputColumnWidth of each column of the text file in the Advanced option on the second page of the Import and Export Wizard to make them consistent, and then you can import. This step will take some time.