语句如下：

    1. create_index_stmt:
    2.       CREATE [UNIQUE] INDEX index_name
    3.       ON table_name (column_desc_list) [index_type]
    4.       [index_option_list];
    5.     | CREATE FULLTEXT INDEX index_name
    6.       ON table_name (column_name_list) CTXCAT(column_name_list)    
    7.       [index_option_list];
    9. drop_index_stmt:
    10.     DROP INDEX index_name ON table_name;
    12. column_desc_list:
    13.     column_desc [, column_desc ...]
    15. column_desc:
    16.     column_name [(length)] [ASC]
    18. index_type:
    19.     USING BTREE
    21. index_option_list:
    22.     index_option [index_option ...]
    24. index_option:
    25.       [GLOBAL | LOCAL]
    26.     | block_size
    27.     | compression
    28.     | STORING(column_name_list)
    29.     | comment
    31. column_name_list:
    32.     column_name [, column_name ...]