STATEMENT

STATEMENT obtains information about execution statements (unique SQL statements) on the current node. To query this view, you must have the sysadmin permission. You can view all statistics about unique SQL statements received by the primary database node and other database nodes, whereas you can view only the statistics about unique SQL statements executed on other database nodes.

Table 1 STATEMENT columns

Name

Type

Description

node_name

name

Database process name

node_id

integer

Node ID (node_id in pgxc_node)

user_name

name

Username

user_id

oid

OID of the user

unique_sql_id

bigint

ID of the unique SQL statement

query

text

Normalized SQL statement

Note: The length is controlled by track_activity_query_size.

n_calls

bigint

Number of calls

min_elapse_time

bigint

Minimum execution time of the SQL statement in the kernel (unit: μs)

max_elapse_time

bigint

Maximum execution time of the SQL statement in the kernel (unit: μs)

total_elapse_time

bigint

Total execution time of the SQL statement in the kernel (unit: μs)

n_returned_rows

bigint

Number of rows in the result set returned by the SELECT statement

n_tuples_fetched

bigint

Number of rows randomly scanned

n_tuples_returned

bigint

Number of rows sequentially scanned

n_tuples_inserted

bigint

Number of rows inserted

n_tuples_updated

bigint

Number of rows updated

n_tuples_deleted

bigint

Number of rows deleted

n_blocks_fetched

bigint

Number of buffer block access times

n_blocks_hit

bigint

Number of buffer block hits

n_soft_parse

bigint

Number of soft parsing times. The value of n_soft_parse plus the value of n_hard_parse may be greater than the value of n_calls because the number of subqueries is not counted in the value of n_calls.

n_hard_parse

bigint

Number of hard parsing times. The value of n_soft_parse plus the value of n_hard_parse may be greater than the value of n_calls because the number of subqueries is not counted in the value of n_calls.

db_time

bigint

Valid DB time, which is accumulated if multiple threads are involved (unit: μs)

cpu_time

bigint

CPU time (unit: μs)

execution_time

bigint

Execution time in the executor (unit: μs)

parse_time

bigint

SQL parsing time (unit: μs)

plan_time

bigint

SQL plan generation time (unit: μs)

rewrite_time

bigint

SQL rewriting time (unit: μs)

pl_execution_time

bigint

Execution time of PL/pgSQL (unit: μs)

pl_compilation_time

bigint

Compilation time of PL/pgSQL (unit: μs)

data_io_time

bigint

I/O time (unit: μs)

net_send_info

text

Network status of messages sent through a physical connection, including the time (unit: μs), number of calls, and throughput (unit: byte). This column can be used to analyze the network overhead of SQL in a distributed system. This column is not supported in a standalone mode. Example: {"time":xxx, "n_calls":xxx, "size":xxx}.

net_recv_info

text

Network status of messages received through a physical connection, including the time (unit: μs), number of calls, and throughput (unit: byte). This column can be used to analyze the network overhead of SQL in a distributed system. This column is not supported in a standalone mode. Example: {"time":xxx, "n_calls":xxx, "size":xxx}.

net_stream_send_info

text

Network status of messages sent through a logical connection, including the time (unit: μs), number of calls, and throughput (unit: byte). This column can be used to analyze the network overhead of SQL in a distributed system. This column is not supported in a standalone mode. Example: {"time":xxx, "n_calls":xxx, "size":xxx}.

net_stream_recv_info

text

Network status of messages received through a logical connection, including the time (unit: μs), number of calls, and throughput (unit: byte). This column can be used to analyze the network overhead of SQL in a distributed system. This column is not supported in a standalone mode. Example: {"time":xxx, "n_calls":xxx, "size":xxx}.

sort_count

bigint

Sorting count

sort_time

bigint

Sorting duration (unit: μs)

sort_mem_used

bigint

Size of work memory used during sorting (unit: KB)

sort_spill_count

bigint

Count of file writing when data is flushed to disks during sorting

sort_spill_size

bigint

File size used when data is flushed to disks during sorting (unit: KB)

hash_count

bigint

Hashing count

hash_time

bigint

Hashing duration (unit: μs)

hash_mem_used

bigint

Size of work memory used during hashing (unit: KB)

hash_spill_count

bigint

Count of file writing when data is flushed to disks during hashing

hash_spill_size

bigint

File size used when data is flushed to disks during hashing (unit: KB)

This feature corresponds to the system function get_instr_unique_sql, which is used to store status records of SQL statements that run after the database is started.

General usage syntax:

openGauss=# select * from dbe_perf.statement;

It is mainly controlled by the following parameters:

  • enable_resource_track: tracks resource usage at runtime.

  • instr_unique_sql_count: indicates the total number of SQL statements that can be recorded in the memory. Each time this parameter is modified, all unique SQL statements in the memory are reset.

  • instr_unique_sql_track_type: indicates the unique SQL tracing mode. The value can be top or all. Currently, only top is supported. For stored procedures, only the outermost call is recorded.

  • enable_auto_clean_unique_sql: indicates whether to enable the auto cleanup mechanism of unique SQL. It can automatically clean up 10% of the records randomly when the upper limit is reached. If it is not enabled, error logs will be recorded and SQL related content will not be recorded in memory.

For details, see GUC parameter: Query.

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