This script will provide the first four values required for estimating the size of a database table. It will satisfy steps one and two in MS estimation process for the amount of space required to store the data in a MS SQL Server v7.0 or v2000 table:
1 Specify the number of rows present in the table:
Number of rows in the table = Num_Rows
2 If there are fixed-length and variable-length columns in the table definition, calculate the space that each of these groups of columns occupies within the data row. The size of a column depends on the data type and length specification. For more information, see Data Types.
Number of columns = Num_Cols
Sum of bytes in all fixed-length columns = Fixed_Data_Size
Number of variable-length columns = Num_Variable_Cols
Maximum size of all variable-length columns = Max_Var_Size
When doing bulk data changes it may be beneficial to disable indexes prior to starting the operation. Fortunately, SQL's rich metadata makes this very easy to automate in a robust fashion.