把数据库从1.9.3+ (Build: 20081126) (2007101532)版升级到1.9.3+ (Build: 20090107) (2007101533.01)版时出错，提示信息如下：
把数据库从1.9.3+ (Build: 20081126) (2007101532)版升级到1.9.3+ (Build: 20090107) (2007101533.01)版...
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(mysql): SELECT r.* FROM mdl_role r, mdl_role_capabilities rc WHERE rc.capability = 'moodle/course:update' AND rc.roleid = r.id AND (rc.contextid = '1' OR rc.contextid IN (1)) AND rc.permission = '1'
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2006: MySQL server has gone away
ADOConnection._Execute(SELECT r.* FROM mdl_role r, mdl_role_capabilities rc WHERE..., false) % line 891, file: adodb.inc.php ADOConnection.Execute(SELECT r.* FROM mdl_role r, mdl_role_capabilities rc WHERE...) % line 683, file: dmllib.php
get_recordset_sql(SELECT r.* FROM mdl_role r, mdl_role_capabilities rc WHERE..., , ) % line 966, file: dmllib.php
get_records_sql(SELECT r.* FROM mdl_role r, mdl_role_capabilities rc WHERE...) % line 2846, file: accesslib.php get_roles_with_capability(moodle/course:update, 1, Object:stdClass) % line 3082, file: upgrade.php
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(mysql): SELECT * FROM mdl_cache_flags WHERE name = '/1' AND flagtype = 'accesslib/dirtycontexts' LIMIT 1
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2006: MySQL server has gone away
ADOConnection._Execute(SELECT * FROM mdl_cache_flags WHERE name = '/1' AND flagtype = 'accesslib/dirtycontexts' LIMIT 1, false) % line 891, file: adodb.inc.php
ADOConnection.Execute(SELECT * FROM mdl_cache_flags WHERE name = '/1' AND flagtype = 'accesslib/dirtycontexts' LIMIT 1, false) % line 498, file: adodb-mysql.inc.php
ADODB_mysql.SelectLimit(SELECT * FROM mdl_cache_flags WHERE name = '/1' AND flagtype = 'accesslib/dirtycontexts', 1, -1) % line 681, file: dmllib.php
get_recordset_sql(SELECT * FROM mdl_cache_flags WHERE name = '/1' AND flagtype = 'accesslib/dirtycontexts', 0, 1) % line 481, file: dmllib.php
get_record_sql(SELECT * FROM mdl_cache_flags WHERE name = '/1' AND flagtype = 'accesslib/dirtycontexts') % line 421, file: dmllib.php
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(mysql): SELECT * FROM mdl_cache_flags WHERE id = '-1'
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2006: MySQL server has gone away
ADOConnection._Execute(SELECT * FROM mdl_cache_flags WHERE id = '-1', false) % line 891, file: adodb.inc.php
ADOConnection.Execute(SELECT * FROM mdl_cache_flags WHERE id = '-1') % line 1469, file: dmllib.php
insert_record(cache_flags, Object:object) % line 853, file: moodlelib.php
set_cache_flag(accesslib/dirtycontexts, /1, 1, 1231434320) % line 5690, file: accesslib.php mark_context_dirty(/1) % line 3090, file: upgrade.php
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(mysql): SELECT name FROM mdl_config WHERE name = 'version' LIMIT 1
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2006: MySQL server has gone away
ADOConnection._Execute(SELECT name FROM mdl_config WHERE name = 'version' LIMIT 1, false) % line 891, file: adodb.inc.php
ADOConnection.Execute(SELECT name FROM mdl_config WHERE name = 'version' LIMIT 1, false) % line 498, file: adodb-mysql.inc.php
ADODB_mysql.SelectLimit(SELECT name FROM mdl_config WHERE name = 'version', 1, -1) % line 681, file: dmllib.php
get_recordset_sql(SELECT name FROM mdl_config WHERE name = 'version', 0, 1) % line 1134, file: dmllib.php
get_field_sql(SELECT name FROM mdl_config WHERE name = 'version') % line 1098, file: dmllib.php
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(mysql): SELECT * FROM mdl_config WHERE id = '-1'
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2006: MySQL server has gone away
ADOConnection._Execute(SELECT * FROM mdl_config WHERE id = '-1', false) % line 891, file: adodb.inc.php
ADOConnection.Execute(SELECT * FROM mdl_config WHERE id = '-1') % line 1469, file: dmllib.php insert_record(config, Object:object) % line 660, file: moodlelib.php set_config(version, 2007101532.1) % line 23, file: adminlib.php upgrade_main_savepoint(true, 2007101532.1) % line 3094, file: upgrade.php
Had trouble upgrading the core capabilities for the Roles System
请问该如何解决？