18 calls to db_add_column() in Drupal 5

system_update_1001 in modules/system/system.install

system_update_1003 in modules/system/system.install

system_update_1006 in modules/system/system.install

system_update_129 in modules/system/system.install

system_update_133 in modules/system/system.install

system_update_139 in modules/system/system.install

system_update_145 in modules/system/system.install

system_update_146 in modules/system/system.install

system_update_148 in modules/system/system.install

system_update_149 in modules/system/system.install

system_update_153 in modules/system/system.install

system_update_154 in modules/system/system.install

system_update_158 in modules/system/system.install

system_update_181 in modules/system/system.install

update_fix_schema_version in ./update.php

If the schema version for Drupal core is stored in the variables table (4.6.x and earlier) move it to the schema_version column of the system table.

update_fix_sessions in ./update.php

System update 130 changes the sessions table, which breaks the update script's ability to use session variables. This changes the table appropriately.

update_fix_system_table in ./update.php

update_fix_watchdog in ./update.php

System update 142 changes the watchdog table, which breaks the update script's ability to use logging. This changes the table appropriately.