6.1 | Introduction 180 |
6.2 | Modifying Tables 180 |
6.2.1 Adding New Columns 180 | |
6.2.2 Controlling the Position of Columns in a Table 182 | |
6.2.3 Changing a Column’s Length 184 | |
6.2.4 Changing a Column’s Format 189 | |
6.2.5 Changing a Column’s Label 189 | |
6.2.6 Renaming a Column 190 | |
6.2.7 Renaming a Table 192 | |
6.3 | Indexes 194 |
6.3.1 Defining Indexes 194 | |
6.3.2 Creating a Simple Index 195 | |
6.3.3 Creating a Composite Index 196 | |
6.3.4 Preventing Duplicate Values in an Index 197 | |
6.3.5 Modifying Columns Containing Indexes 197 | |
6.3.6 Deleting (Dropping) Indexes 198 | |
6.4 | Updating Data in a Table 199 |
6.5 | Summary 200 |