Manual:Querycachetwo table

The querycachetwo table is a table used for caching expensive grouped queries that need two links (for example double-redirects).

qcc_type
A key name, generally the base name of the special page.

qcc_value
Some sort of stored value. Sizes, counts...

qcc_namespace
Target namespace. Used in conjunction with qcc_title.

qcc_title
Target title. Used in conjunction with qcc_namespace.

qcc_namespacetwo
Target namespace2. Used in conjunction with qcc_titletwo.

qcc_titletwo
Target title2. Used in conjunction with qcc_namespacetwo.

Schema summary
+--+--+--+-+-+---+ +--+--+--+-+-+---+ +--+--+--+-+-+---+
 * Field           | Type             | Null | Key | Default | Extra |
 * qcc_type        | varbinary(32)    | NO   | MUL | NULL    |       |
 * qcc_value       | int(10) unsigned | NO   |     | 0       |       |
 * qcc_namespace   | int(11)          | NO   |     | 0       |       |
 * qcc_title       | varbinary(255)   | NO   |     |         |       |
 * qcc_namespacetwo | int(11)         | NO   |     | 0       |       |
 * qcc_titletwo    | varbinary(255)   | NO   |     |         |       |

+--+--+--+-+-+---+ +--+--+--+-+-+---+ +--+--+--+-+-+---+
 * Field           | Type             | Null | Key | Default | Extra |
 * qcc_type        | varbinary(32)    | NO   | MUL | NULL    |       |
 * qcc_value       | int(10) unsigned | NO   |     | 0       |       |
 * qcc_namespace   | int(11)          | NO   |     | 0       |       |
 * qcc_title       | char(255) binary | NO   |     | NULL    |       |
 * qcc_namespacetwo | int(11)         | NO   |     | 0       |       |
 * qcc_titletwo    | char(255) binary | NO   |     | NULL    |       |

+--+--+--+-+-+---+ +--+--+--+-+-+---+ +--+--+--+-+-+---+
 * Field           | Type             | Null | Key | Default | Extra |
 * qcc_type        | char(32)         | NO   | MUL | NULL    |       |
 * qcc_value       | int(5) unsigned  | NO   |     | 0       |       |
 * qcc_namespace   | int(11)          | NO   |     | 0       |       |
 * qcc_title       | char(255) binary | NO   |     | NULL    |       |
 * qcc_namespacetwo | int(11)         | NO   |     | 0       |       |
 * qcc_titletwo    | char(255) binary | NO   |     | NULL    |       |