SHOW TABLET
Description
Displays tablet-related information.
NOTE
This operation requires the ADMIN_PRIV privilege.
Syntax
Query information of tablets in a table or a partition
SHOW TABLET
FROM [<db_name>.]<table_name>
[PARTITION(<partition_name>, ...]
[
WHERE [version = <version_number>]
[[AND] backendid = <backend_id>]
[[AND] STATE = "NORMAL"|"ALTER"|"CLONE"|"DECOMMISSION"]
]
[ORDER BY <field_name> [ASC | DESC]]
[LIMIT [<offset>,]<limit>]
Parameter | Required | Description |
---|---|---|
db_name | No | The database name. If you do not specify this parameter, the current database is used by default. |
table_name | Yes | The name of the table from which you want to query tablet information. You must specify this parameter. Otherwise, an error is returned. |
partition_name | No | The name of the partition from which you want to query tablet information. |
version_number | No | The data version number. |
backend_id | No | The ID of the BE where the replica of the tablet is located. |
STATE | No | The status of tablet replicas.
|
field_name | No | The field by which the results are sorted. All the fields returned by SHOW TABLET FROM <table_name> are sortable.
|
offset | No | The number of tablets to skip from the results. For example, OFFSET 5 means to skip the first five tablets. Default value: 0. |
limit | No | The number of tablets to return. For example, LIMIT 10 means to return only 10 tablets. If this parameter is not specified, all the tablets that meet the filter conditions are returned. |
Query information of a single tablet
After obtaining all tablet IDs using SHOW TABLET FROM <table_name>
, you can query the information of a single tablet.
SHOW TABLET <tablet_id>
Parameter | Required | Description |
---|---|---|
tablet_id | Yes | Tablet ID |
Description of return fields
Query information of tablets in a table or a partition
+----------+-----------+-----------+------------+---------+-------------+-------------------+-----------------------+------------------+----------------------+---------------+----------+----------+--------+-------------------------+--------------+------------------+--------------+----------+----------+-------------------+
| TabletId | ReplicaId | BackendId | SchemaHash | Version | VersionHash | LstSuccessVersion | LstSuccessVersionHash | LstFailedVersion | LstFailedVersionHash | LstFailedTime | DataSize | RowCount | State | LstConsistencyCheckTime | CheckVersion | CheckVersionHash | VersionCount | PathHash | MetaUrl | CompactionStatus |
+----------+-----------+-----------+------------+---------+-------------+-------------------+-----------------------+------------------+----------------------+---------------+----------+----------+--------+-------------------------+--------------+------------------+--------------+----------+----------+-------------------+
Field | Description |
---|---|
TabletId | Table ID. |
ReplicaId | Replica ID. |
BackendId | The ID of the BE where the replica is located. |
SchemaHash | Schema hash (randomly generated). |
Version | Data version number. |
VersionHash | Hash of data version number. |
LstSuccessVersion | The last successfully loaded version. |
LstSuccessVersionHash | The hash of the last successfully loaded version. |
LstFailedVersion | The version of the last failed loading. -1 indicates no version failed to be loaded. |
LstFailedVersionHash | The hash of the last failed version. |
LstFailedTime | The time of the last failed loading. NULL indicates there is no load failure. |
DataSize | Data size of the tablet. |
RowCount | The number of data rows of the tablet. |
State | Replica status of the tablet. |
LstConsistencyCheckTime | The time of the last consistency check. NULL indicates no consistency check was performed. |
CheckVersion | The data version on which consistency check was performed. -1 indicates no version was checked. |
CheckVersionHash | The hash of the version on which consistency check was performed. |
VersionCount | The total number of data versions. |
PathHash | The hash of the directory in which the tablet is stored. |
MetaUrl | The URL used to query more meta information. |
CompactionStatus | The URL used to query data version compaction status. |
Query information of a specific tablet
+--------+-----------+---------------+-----------+------+---------+-------------+---------+--------+-----------+
| DbName | TableName | PartitionName | IndexName | DbId | TableId | PartitionId | IndexId | IsSync | DetailCmd |
+--------+-----------+---------------+-----------+------+---------+-------------+---------+--------+-----------+
Field | Description |
---|---|
DbName | The name of the database to which the tablet belongs. |
TableName | The name of the table to which the tablet belongs. |
PartitionName | The name of the partition to which the tablet belongs. |
IndexName | The index name. |
DbId | The database ID. |
TableId | The table ID. |
PartitionId | The partition ID. |
IndexId | The index ID. |
IsSync | Whether data on the tablet is consistent with table meta. true indicates data is consistent and the tablet is normal. false indicates data is missing on the tablet. |
DetailCmd | The URL used to query more information. |
Examples
Create table test_show_tablet
in the database example_db
.
CREATE TABLE `test_show_tablet` (
`k1` date NULL COMMENT "",
`k2` datetime NULL COMMENT "",
`k3` char(20) NULL COMMENT "",
`k4` varchar(20) NULL COMMENT "",
`k5` boolean NULL COMMENT "",
`k6` tinyint(4) NULL COMMENT "",
`k7` smallint(6) NULL COMMENT "",
`k8` int(11) NULL COMMENT "",
`k9` bigint(20) NULL COMMENT "",
`k10` largeint(40) NULL COMMENT "",
`k11` float NULL COMMENT "",
`k12` double NULL COMMENT "",
`k13` decimal128(27, 9) NULL COMMENT ""
) ENGINE=OLAP
DUPLICATE KEY(`k1`, `k2`, `k3`, `k4`, `k5`)
COMMENT "OLAP"
PARTITION BY RANGE(`k1`)
(PARTITION p20210101 VALUES [("2021-01-01"), ("2021-01-02")),
PARTITION p20210102 VALUES [("2021-01-02"), ("2021-01-03")),
PARTITION p20210103 VALUES [("2021-01-03"), ("2021-01-04")),
PARTITION p20210104 VALUES [("2021-01-04"), ("2021-01-05")),
PARTITION p20210105 VALUES [("2021-01-05"), ("2021-01-06")),
PARTITION p20210106 VALUES [("2021-01-06"), ("2021-01-07")),
PARTITION p20210107 VALUES [("2021-01-07"), ("2021-01-08")),
PARTITION p20210108 VALUES [("2021-01-08"), ("2021-01-09")),
PARTITION p20210109 VALUES [("2021-01-09"), ("2021-01-10")))
DISTRIBUTED BY HASH(`k1`, `k2`, `k3`);
-
Example 1: Query information of all the tablets in the specified table. The following example excerpts information of only one tablet from the return information.
mysql> show tablet from example_db.test_show_tablet\G
*************************** 1. row ***************************
TabletId: 9588955
ReplicaId: 9588956
BackendId: 10004
SchemaHash: 0
Version: 1
VersionHash: 0
LstSuccessVersion: 1
LstSuccessVersionHash: 0
LstFailedVersion: -1
LstFailedVersionHash: 0
LstFailedTime: NULL
DataSize: 0B
RowCount: 0
State: NORMAL
LstConsistencyCheckTime: NULL
CheckVersion: -1
CheckVersionHash: 0
VersionCount: 1
PathHash: 0
MetaUrl: http://172.26.92.141:8038/api/meta/header/9588955
CompactionStatus: http://172.26.92.141:8038/api/compaction/show?tablet_id=9588955 -
Example 2: Query information of tablet 9588955.
mysql> show tablet 9588955\G
*************************** 1. row ***************************
DbName: example_db
TableName: test_show_tablet
PartitionName: p20210103
IndexName: test_show_tablet
DbId: 11145
TableId: 9588953
PartitionId: 9588946
IndexId: 9588954
IsSync: true
DetailCmd: SHOW PROC '/dbs/11145/9588953/partitions/9588946/9588954/9588955'; -
Example 3: Query information of tablets in partition
p20210103
.SHOW TABLET FROM test_show_tablet partition(p20210103);
-
Example 4: Return information of 10 tablets.
SHOW TABLET FROM test_show_tablet limit 10;
-
Example 5: Return information of 10 tablets with an offset 5.
SHOW TABLET FROM test_show_tablet limit 5,10;
-
Example 6: Filter tablets by
backendid
,version
, andstate
.SHOW TABLET FROM test_show_tablet
WHERE backendid = 10004 and version = 1 and state = "NORMAL"; -
Example 7: Sort tablets by
version
.SHOW TABLET FROM table_name where backendid = 10004 order by version;
-
Example 8: Return information of tablets whose index name is
test_show_tablet
.SHOW TABLET FROM test_show_tablet where indexname = "test_show_tablet";