SHOW [FULL] STATS
查看整体的统计信息，这些信息都是瞬时值。 注意不同版本的PolarDB-XSHOW FULL STATS的结果是有区别的。
示例：
mysql> show stats; +------+---------+----------+-------------------+------------------+------------------------+--------------------+--------+------------+--------------+---------------+----------------+---------------+---------------+--------------+ | QPS | RDS_QPS | SLOW_QPS | PHYSICAL_SLOW_QPS | ERROR_PER_SECOND | MERGE_QUERY_PER_SECOND | ACTIVE_CONNECTIONS | RT(MS) | RDS_RT(MS) | NET_IN(KB/S) | NET_OUT(KB/S) | THREAD_RUNNING | DDL_JOB_COUNT | BACKFILL_ROWS | CHECKED_ROWS | +------+---------+----------+-------------------+------------------+------------------------+--------------------+--------+------------+--------------+---------------+----------------+---------------+---------------+--------------+ | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 0.00 | 1 | 0.00 | 0.00 | 0.00 | 0.00 | 1 | 0 | 0 | 0 | +------+---------+----------+-------------------+------------------+------------------------+--------------------+--------+------------+--------------+---------------+----------------+---------------+---------------+--------------+ mysql> show full stats; +------+---------+----------+-------------------+------------------+----------------------+------------------------+--------------------+------------------------------+--------+------------+--------------+---------------+----------------+----------------------+-----------------+----------------------------+-----------------------+------------------------------+-------------------------+--------------------------+---------------------+-------+---------+-------------+------------+ | QPS | RDS_QPS | SLOW_QPS | PHYSICAL_SLOW_QPS | ERROR_PER_SECOND | VIOLATION_PER_SECOND | MERGE_QUERY_PER_SECOND | ACTIVE_CONNECTIONS | CONNECTION_CREATE_PER_SECOND | RT(MS) | RDS_RT(MS) | NET_IN(KB/S) | NET_OUT(KB/S) | THREAD_RUNNING | HINT_USED_PER_SECOND | HINT_USED_COUNT | AGGREGATE_QUERY_PER_SECOND | AGGREGATE_QUERY_COUNT | TEMP_TABLE_CREATE_PER_SECOND | TEMP_TABLE_CREATE_COUNT | MULTI_DB_JOIN_PER_SECOND | MULTI_DB_JOIN_COUNT | CPU | FREEMEM | FULLGCCOUNT | FULLGCTIME | +------+---------+----------+-------------------+------------------+----------------------+------------------------+--------------------+------------------------------+--------+------------+--------------+---------------+----------------+----------------------+-----------------+----------------------------+-----------------------+------------------------------+-------------------------+--------------------------+---------------------+-------+---------+-------------+------------+ | 1.63 | 1.68 | 0.03 | 0.03 | 0.02 | 0.00 | 0.00 | 6 | 0.01 | 157.13 | 51.14 | 134.33 | 1.21 | 1 | 0.00 | 54 | 0.00 | 663 | 0.00 | 512 | 0.00 | 516 | 0.09% | 6.96% | 76446 | 21326906 | +------+---------+----------+-------------------+------------------+----------------------+------------------------+--------------------+------------------------------+--------+------------+--------------+---------------+----------------+----------------------+-----------------+----------------------------+-----------------------+------------------------------+-------------------------+--------------------------+---------------------+-------+---------+-------------+------------+ 1 row in set (0.01 sec)
重要列说明：
- QPS：应用到PolarDB-X的QPS，通常称为逻辑QPS；
- RDS_QPS：PolarDB-X到RDS的QPS，通常称为物理QPS；
- ERROR_PER_SECOND：每秒的错误数，包含SQL语法错误，主键冲突，系统错误，连通性错误等各类错误总和；
- VIOLATION_PER_SECOND：每秒的主键或者唯一键冲突；
- MERGE_QUERY_PER_SECCOND：通过分库分表，从多表中进行的查询；
- ACTIVE_CONNECTIONS：正在使用的连接；
- CONNECTION_CREATE_PER_SECCOND：每秒创建的连接数；
- RT(MS)：应用到PolarDB-X的响应时间，通常称为逻辑RT（响应时间）；
- RDS_RT(MS)：PolarDB-X到RDS/MySQL的响应时间，通常称为物理RT；
- NET_IN(KB/S)：PolarDB-X收到的网络流量；
- NET_OUT(KB/S)：PolarDB-X输出的网络流量；
- THREAD_RUNNING：正在运行的线程数；
- HINT_USED_PER_SECOND：每秒带HINT的查询的数量；
- HINT_USED_COUNT：启动到现在带HINT的查询总量；
- AGGREGATE_QUERY_PER_SECCOND：每秒聚合查询的频次；
- AGGREGATE_QUERY_COUNT：聚合查询总数（历史累计数据）；
- TEMP_TABLE_CREATE_PER_SECCOND：每秒创建的临时表的数量；
- TEMP_TABLE_CREATE_COUNT：启动到现在创建的临时表总数量；
- MULTI_DB_JOIN_PER_SECCOND：每秒跨库JOIN的数量；
- MULTI_DB_JOIN_COUNT：启动到现在跨库JOIN的总量。
SHOW DB STATUS
用于查看物理库容量/性能信息，所有返回值为实时信息。 容量信息通过MySQL系统表获得，与真实容量情况可能有差异。
示例：
mysql> show db status;
+------+---------------------------+--------------------+-------------------+------------+--------+----------------+| ID | NAME | CONNECTION_STRING | PHYSICAL_DB | SIZE_IN_MB | RATIO | THREAD_RUNNING |
+------+---------------------------+--------------------+-------------------+------------+--------+----------------+
| 1 | drds_db_1516187088365daui | 100.100.64.1:59077 | TOTAL | 13.109375 | 100% | 3 |
| 2 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0000 | 1.578125 | 12.04% | |
| 3 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0001 | 1.4375 | 10.97% | |
| 4 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0002 | 1.4375 | 10.97% | |
| 5 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0003 | 1.4375 | 10.97% | |
| 6 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0004 | 1.734375 | 13.23% | |
| 7 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0005 | 1.734375 | 13.23% | |
| 8 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0006 | 2.015625 | 15.38% | |
| 9 | drds_db_1516187088365daui | 100.100.64.1:59077 | drds_db_xzip_0007 | 1.734375 | 13.23% | |
+------+---------------------------+--------------------+-------------------+------------+--------+----------------+
重要列说明：
- NAME：代表一个PolarDB-XDB，此处显示的是PolarDB-X内部标记，与PolarDB-XDB名称不同；
- CONNECTION_STRING：分库的连接信息；
- PHYSICAL_DB：分库名称，
TOTAL行代表一个PolarDB-XDB中所有分库容量的总和； - SIZE_IN_MB：分库中数据占用的空间，单位为MB；
- RATIO：单个分库数据量在当前PolarDB-XDB总数据量中的占比；
- THREAD_RUNNING：物理数据库实例当前正在执行的线程情况，含义与MySQL语句
SHOW GLOBAL STATUS返回值的含义相同。
SHOW TABLE STATUS
获取表的信息，该指令聚合了底层各个物理分表的数据。
示例：
mysql> SHOW TABLE STATUS;
+---------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+--------------------+----------+----------------+---------+
| NAME | ENGINE | VERSION | ROW_FORMAT | ROWS | AVG_ROW_LENGTH | DATA_LENGTH | MAX_DATA_LENGTH | INDEX_LENGTH | DATA_FREE | AUTO_INCREMENT | CREATE_TIME | UPDATE_TIME | CHECK_TIME | COLLATION | CHECKSUM | CREATE_OPTIONS | COMMENT |
+---------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+--------------------+----------+----------------+---------+
| sbtest1 | InnoDB | 10 | Dynamic | 0 | 0 | 1310720 | 0 | 0 | 0 | 0 | 2021-07-20 15:39:37 | NULL | NULL | utf8mb4_general_ci | NULL | | |
| t1 | InnoDB | 10 | Dynamic | 0 | 0 | 2621440 | 0 | 2621440 | 0 | 200000 | 2021-07-26 20:11:15 | NULL | NULL | utf8mb4_general_ci | NULL | | |
+---------+--------+---------+------------+------+----------------+-------------+-----------------+--------------+-----------+----------------+---------------------+-------------+------------+--------------------+----------+----------------+---------+
重要列详解：
- NAME：表名称；
- ENGINE：表的存储引擎；
- VERSION：表的存储引擎的版本；
- ROW_FORMAT：行格式，主要是Dynamic、Fixed、Compressed这三种格式。动态（Dynamic）行的行长度可变，例如VARCHAR或BLOB类型字段；固定（Fixed）行是指行长度不变，例如CHAR和INTEGER类型字段；
- ROWS：表中的行数；
- AVG_ROW_LENGTH：平均每行包括的字节数；
- DATA_LENGTH：整个表的数据量（单位：字节）；
- MAX_DATA_LENGTH：表可以容纳的最大数据量；
- INDEX_LENGTH：索引占用磁盘的空间大小 ；
- CREATE_TIME：表的创建时间；
- UPDATE_TIME：表的最近更新时间；
- COLLATION：表的默认字符集和字符排序规则；
- CREATE_OPTIONS：指表创建时的其他所有选项。
SHOW TABLE INFO [name]
获取各个分表的数据量信息。
示例：
mysql> show table info sbtest1;
+----+--------------+-----------------+------------+
| ID | GROUP_NAME | TABLE_NAME | SIZE_IN_MB |
+----+--------------+-----------------+------------+
| 0 | test1_000000 | sbtest1_wo5k_00 | 0.01562500 |
| 1 | test1_000000 | sbtest1_wo5k_01 | 0.01562500 |
| 2 | test1_000005 | sbtest1_wo5k_10 | 0.01562500 |
| 3 | test1_000005 | sbtest1_wo5k_11 | 0.01562500 |
| 4 | test1_000010 | sbtest1_wo5k_20 | 0.01562500 |
| 5 | test1_000010 | sbtest1_wo5k_21 | 0.01562500 |
| 6 | test1_000015 | sbtest1_wo5k_30 | 0.01562500 |
| 7 | test1_000015 | sbtest1_wo5k_31 | 0.01562500 |
| 8 | test1_000020 | sbtest1_wo5k_40 | 0.01562500 |
| 9 | test1_000020 | sbtest1_wo5k_41 | 0.01562500 |
| 10 | test1_000025 | sbtest1_wo5k_50 | 0.01562500 |
| 11 | test1_000025 | sbtest1_wo5k_51 | 0.01562500 |
| 12 | test1_000030 | sbtest1_wo5k_60 | 0.01562500 |
| 13 | test1_000030 | sbtest1_wo5k_61 | 0.01562500 |
| 14 | test1_000035 | sbtest1_wo5k_70 | 0.01562500 |
| 15 | test1_000035 | sbtest1_wo5k_71 | 0.01562500 |
+----+--------------+-----------------+------------+
重要列详解：
- ID：标识；
- GROUP_NAME：分库名；
- TABLE_NAME：物理分表名；
- SIZE_IN_MB：表大小；
