SQL Server database system collation--creation and management of data tables

Attention:

1. Fixed-length character types take up more space than non-fixed-length character types, but because the fixed-length character type is not required for length processing when setting the field value, it is faster to process. Therefore, the use of fixed-length character types will improve system performance for relatively fixed length data.

2, modify the existing data table, add the syntax of the field: ALTER table name to be modified Add field name segment type

3, modify the existing data table, delete the syntax of the field: ALTER table name to be modified drop the field name to be deleted

4. Syntax for deleting data tables: Drop table name to delete