Querying Metadata Locks

Function

Query metadata locks. Currently, this function is supported only for MySQL DB instances.

URI

GET /v3/{project_id}/instances/{instance_id}/metadata-locks

**Table 1** Path parameters
Parameter	Mandatory	Type	Description
project_id	Yes	String	Project ID. To obtain this value, see Obtaining a Project ID.
instance_id	Yes	String	Instance ID.

**Table 2** Query parameters
Parameter	Mandatory	Type	Description
db_user_id	Yes	String	Database user ID
thread_id	No	String	Session ID
database	No	String	Database name
table	No	String	Table name

Request Parameters

**Table 3** Request header parameters
Parameter	Mandatory	Type	Description
X-Auth-Token	Yes	String	User token.
X-Language	No	String	Language. The value can be: zh-cn en-us

Response Parameters

Status code: 200

**Table 4** Response body parameters
Parameter	Type	Description
metadata_locks	Array of MetadataLock objects	List of metadata locks.
count	Integer	Number of metadata locks.

**Table 5** MetadataLock
Parameter	Type	Description
thread_id	String	Session ID.
lock_status	String	Lock status. The value can be PENDING (lock wait) or GRANTED (held lock).
lock_mode	String	Metadata lock (MDL) mode. The value can be MDL_SHARED, MDL_EXCLUSIVE, MDL_SHARED_READ, or MDL_SHARED_WRITE.
lock_type	String	Lock type. The value can be Table metadata lock, Schema metadata lock, Tablespace lock, or Global read lock.
lock_duration	String	Lock scope. The value can be MDL_STATEMENT (statement-level), MDL_TRANSACTION (transaction level), or MDL_EXPLICIT (global).
table_schema	String	Database where the lock exists. This field is left blank for some global read metadata locks.
table_name	String	Table name.
user	String	User.
time	String	Time.
host	String	Host.
database	String	Database that the session belongs to.
command	String	Command.
state	String	Status.
sql	String	SQL statement.
trx_exec_time	String	Time when the transaction was executed.
block_process	Array of Process objects	List of blocked sessions.
wait_process	Array of Process objects	List of waiting sessions.

**Table 6** Process
Parameter	Type	Description
id	String	Session ID.
user	String	User.
host	String	Host.
database	String	Database.
command	String	Command.
time	String	Session duration.
state	String	Status.
sql	String	SQL statement.
trx_executed_time	String	Transaction duration.

Status code: 400

**Table 7** Response body parameters
Parameter	Type	Description
error_code	String	Error code. Minimum length: 8 Maximum length: 36
error_msg	String	Error message. Minimum length: 2 Maximum length: 512

Status code: 500

**Table 8** Response body parameters
Parameter	Type	Description
error_code	String	Error code. Minimum length: 8 Maximum length: 36
error_msg	String	Error message. Minimum length: 2 Maximum length: 512

Example Requests

Querying metadata locks

GET https://das.cn-north-1.myhuaweicloud.com/v3/054e292c9880d4992f02c0196d3ea468/instances/da304cd5bbb944de828759bc7be3d3fein01/metadata-locks?db_user_id=2c250598-1e3c-4d31-bc19-be1d866247e6&thread_id=12121&database=example&table=example

Example Responses

Status code: 200

{
  "metadata_locks" : [ {
    "thread_id" : "4096619",
    "lock_status" : "GRANTED",
    "lock_mode" : "MDL_SHARED_READ",
    "lock_type" : "Table metadata lock",
    "lock_duration" : "MDL_TRANSACTION",
    "table_schema" : "test_zyr",
    "table_name" : "test2",
    "user" : "root",
    "time" : "40",
    "host" : "das server",
    "database" : "test_zyr",
    "command" : "Sleep",
    "state" : "",
    "sql" : null,
    "trx_exec_time" : "341",
    "block_process" : [ ],
    "wait_process" : [ ]
  } ],
  "count" : 1
}