add a few more indexes. This is just a first step. More work is needed here but this should improve perfomance already for big installations.

db_structure.xml

@@ -46,6 +46,13 @@
 					<sorting>ascending</sorting>
 				</field>
 			</index>
+			<index>
+				<name>appconfig_config_key_index</name>
+				<field>
+					<name>configkey</name>
+					<sorting>ascending</sorting>
+				</field>
+			</index>
 
 		</declaration>
 
@@ -257,6 +264,13 @@
 				<notnull>true</notnull>
 				<length>64</length>
 			</field>
+			<index>
+				<name>group_admin_uid</name>
+				<field>
+					<name>uid</name>
+					<sorting>ascending</sorting>
+				</field>
+			</index>
 
 		</declaration>
 
@@ -580,6 +594,21 @@
 				<default></default>
 				<notnull>false</notnull>
 			</field>
+			<index>
+				<name>share_file_target_index</name>
+				<field>
+					<name>file_target</name>
+					<sorting>ascending</sorting>
+				</field>
+				<field>
+					<name>uid_owner</name>
+					<sorting>ascending</sorting>
+				</field>
+				<field>
+					<name>share_type</name>
+					<sorting>ascending</sorting>
+				</field>
+			</index>
 
 		</declaration>