Clear the zabbix history cache
Mysql > use zabbix
Displays the table size in the zabbix database
Mysql > SELECT table_name AS "Tables", round ((data_length + index_length) / 1024 / 1024), 2) "Size in MB" FROM information_schema.TABLES WHERE table_schema = 'zabbix' ORDER BY (data_length + index_length) DESC
+-+ +
| | Tables | Size in MB |
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| | history_uint | 887.00 | |
| | history | 674.05 | |
| | trends_uint | 22.38 |
| | trends | 19.39 |
| | events | 4.55 | |
| | images | 1.53 |
| | items | 0.72 |
| | history_str | 0.33 |
| | alerts | 0.25 | |
| | items_applications | 0.23 |
| | profiles | 0.22 |
| | auditlog | 0.17 | |
| | triggers | 0.14 |
| | graphs | 0.13 |
| | hosts | 0.11 |
| | graphs_items | 0.11 |
| | sysmaps_elements | 0.09 |
| | item_discovery | 0.09 |
| | sysmaps | 0.08 |
| | httptest | 0.08 |
| | functions | 0.08 |
| | sysmaps_links | 0.06 |
| | acknowledges | 0.06 |
| | group_prototype | 0.06 |
| | scripts | 0.06 |
| | actions | 0.06 |
| | slideshows | 0.05 | |
| | config | 0.05 | |
| | item_application_prototype | 0.05 | |
| | slideshow_usrgrp | 0.05 | |
| | sysmaps_link_triggers | 0.05 | |
| | optemplate | 0.05 | |
| | hosts_templates | 0.05 | |
| | slideshow_user | 0.05 | |
| | media | 0.05 | |
| | opmessage_usr | 0.05 | |
| | hosts_groups | 0.05 | |
| | users_groups | 0.05 | |
| | interface | 0.05 | |
| | slides | 0.05 | |
| | screens | 0.05 | |
| | dservices | 0.05 | |
| | opmessage_grp | 0.05 | |
| | maintenances_windows | 0.05 | |
| | screen_usrgrp | 0.05 | |
| | sysmap_usrgrp | 0.05 | |
| | drules | 0.05 | |
| | maintenances_hosts | 0.05 | |
| | screen_user | 0.05 | |
| | icon_mapping | 0.05 | |
| | opgroup | 0.05 | |
| | rights | 0.05 | |
| | services_links | 0.05 | |
| | maintenances_groups | 0.05 | |
| | application_template | 0.05 | |
| | host_discovery | 0.05 | |
| | icon_map | 0.05 | |
| | trigger_depends | 0.05 | |
| | application_prototype | 0.05 | |
| | httptestitem | 0.05 | |
| | sysmap_user | 0.05 | |
| | service_alarms | 0.05 | |
| | application_discovery | 0.05 | |
| | history_text | 0.05 | |
| | opcommand_hst | 0.05 | |
| | httpstepitem | 0.05 | |
| | opcommand_grp | 0.05 | |
| | httpstep | 0.03 |
| | opcommand | 0.03 |
| | expressions | 0.03 |
| | media_type | 0.03 |
| | conditions | 0.03 |
| | usrgrp | 0.03 |
| | groups | 0.03 |
| | interface_discovery | 0.03 |
| | autoreg_host | 0.03 |
| | escalations | 0.03 |
| | mappings | 0.03 |
| | group_discovery | 0.03 |
| | auditlog_details | 0.03 |
| | users | 0.03 |
| | sessions | 0.03 |
| | opmessage | 0.03 |
| | hostmacro | 0.03 |
| | services_times | 0.03 |
| | dhosts | 0.03 |
| | applications | 0.03 |
| | trigger_discovery | 0.03 |
| | graph_theme | 0.03 |
| | operations | 0.03 |
| | services | 0.03 |
| | graph_discovery | 0.03 |
| | regexps | 0.03 |
| | opconditions | 0.03 |
| | sysmap_url | 0.03 |
| | valuemaps | 0.03 |
| | dchecks | 0.03 |
| | sysmap_element_url | 0.03 |
| | screens_items | 0.03 |
| | item_condition | 0.03 |
| | housekeeper | 0.02 |
| | ids | 0.02 |
| | opinventory | 0.02 |
| | host_inventory | 0.02 |
| | maintenances | 0.02 |
| | globalvars | 0.02 |
| | proxy_history | 0.02 |
| | globalmacro | 0.02 |
| | proxy_dhistory | 0.02 |
| | timeperiods | 0.02 |
| | proxy_autoreg_host | 0.02 |
| | dbversion | 0.02 |
| | history_log | 0.02 |
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113 rows in set (0.14 sec)
Describe the table structure:
Mysql > desc history_uint
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| | Field | Type | Null | Key | Default | Extra | |
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| | itemid | bigint (20) unsigned | NO | MUL | NULL |
| | clock | int (11) | NO | | 0 | |
| | value | bigint (20) unsigned | NO | | 0 | |
| | ns | int (11) | NO | | 0 | |
+-+ +
4 rows in set (0.00 sec)
Clear the history cache:
Mysql > truncate table history
Query OK, 0 rows affected (0.15 sec)
Mysql > truncate table history_uint
Query OK, 0 rows affected (0.13 sec)
Sometimes we need to clear all the data in a table. One way to achieve this goal is the DROP TABLE instruction that we see on the SQL DROP page. But then the whole form disappears and can no longer be used. Another way is to use TRUNCATE TABLE instructions. Under this instruction, the data in the table will disappear completely, but the table itself will continue to exist. The syntax of TRUNCATE TABLE is as follows:
TRUNCATE TABLE "form name"
So, if we want to clear the data from the customer form created on the SQL Create Table page, we type in:
TRUNCATE TABLE Customer
