mysql> describe cdr;
+-------------+--------------+------+-----+---------------------+----------------+
| Field       | Type         | Null | Key | Default             | Extra          |
+-------------+--------------+------+-----+---------------------+----------------+
| id          | int(11)      |      | PRI | NULL                | auto_increment |
| calldate    | datetime     |      |     | 0000-00-00 00:00:00 |                |
| clid        | varchar(80)  |      |     |                     |                |
| src         | varchar(80)  |      | MUL |                     |                |
| dst         | varchar(80)  |      | MUL |                     |                |
| dcontext    | varchar(80)  |      |     |                     |                |
| channel     | varchar(80)  |      |     |                     |                |
| dstchannel  | varchar(80)  |      |     |                     |                |
| lastapp     | varchar(80)  |      |     |                     |                |
| lastdata    | varchar(80)  |      |     |                     |                |
| duration    | int(11)      |      |     | 0                   |                |
| billsec     | int(11)      |      |     | 0                   |                |
| disposition | varchar(45)  |      |     |                     |                |
| amaflags    | int(11)      |      |     | 0                   |                |
| accountcode | varchar(20)  |      |     |                     |                |
| uniqueid    | varchar(32)  |      |     |                     |                |
| userfield   | varchar(255) |      |     |                     |                |
+-------------+--------------+------+-----+---------------------+----------------+
17 rows in set (0.00 sec)

mysql> show index from cdr;
+-------+------------+-------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
| Table | Non_unique | Key_name    | Seq_in_index | Column_name | Collation | Cardinality | Sub_part | Packed | Null | Index_type | Comment |
+-------+------------+-------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
| cdr   |          0 | PRIMARY     |            1 | id          | A         |     1000657 |     NULL | NULL   |      | BTREE      |         |
| cdr   |          1 | cdr_src_idx |            1 | src         | A         |       58862 |     NULL | NULL   |      | BTREE      |         |
| cdr   |          1 | cdr_dst_idx |            1 | dst         | A         |      111184 |     NULL | NULL   |      | BTREE      |         |
+-------+------------+-------------+--------------+-------------+-----------+-------------+----------+--------+------+------------+---------+
3 rows in set (0.00 sec)

mysql> explain SELECT calldate,src,dst,billsec,disposition FROM cdr WHERE src = '21972829' OR dst = '21972829';+-------+------+-------------------------+------+---------+------+---------+-------------+
| table | type | possible_keys           | key  | key_len | ref  | rows    | Extra       |
+-------+------+-------------------------+------+---------+------+---------+-------------+
| cdr   | ALL  | cdr_src_idx,cdr_dst_idx | NULL |    NULL | NULL | 1000677 | Using where |
+-------+------+-------------------------+------+---------+------+---------+-------------+
1 row in set (0.00 sec)

mysql> explain SELECT calldate,src,dst,billsec,disposition FROM cdr force index(cdr_src_idx,cdr_dst_idx) WHERE src = '21972829' OR dst = '21972829';
+-------+------+-------------------------+------+---------+------+---------+-------------+
| table | type | possible_keys           | key  | key_len | ref  | rows    | Extra       |
+-------+------+-------------------------+------+---------+------+---------+-------------+
| cdr   | ALL  | cdr_src_idx,cdr_dst_idx | NULL |    NULL | NULL | 1000677 | Using where |
+-------+------+-------------------------+------+---------+------+---------+-------------+
1 row in set (0.00 sec)