| Length of a table name | 1~255 Bytes | The name of a table can contain letters, digits, and underscores (_). The name must start with a letter or an underscore (_). |
| Number of secondary indexes that are created for a table | 5 | A maximum of five index tables can be created for each data table. |
| Number of index columns | 1 to 4 | You can add up to four index columns to an index table. Index columns in an index table are a combination of primary key columns and predefined columns of the data table for which the index table is created. |
| Number of primary key columns | 8 | The primary key of an index table consists of index columns and all primary key columns of the data table for which the index table is created. |
| Data types supported by index columns | STRING, INTEGER, and BINARY | The data types supported by index columns are STRING, INTEGER, and BINARY. |
| Number of attribute columns | 32 | You can add up to 32 attribute columns to an index table. Attribute columns in an index table are a combination of predefined columns of the data table for which the index table is created. |
| Data types supported by attribute columns | STRING, INTEGER, DOUBLE, BOOLEAN, and BINARY | The data types supported by attribute columns are STRING, INTEGER, DOUBLE, BOOLEAN, and BINARY. |