[YSQL] Enhancement to pg_stat_statment

[sushantrmishra]

Jira Link: DB-4447

Description

Enhancement to pg_stat_statment :

Name	Type	Description	Comments
storage_rows_read	bigint	Total number of rows read in storage layer	rows tracks the rows returned or written. With storage_rows_read/storage_filtered_rows/query_filtered_rows shows the complete execution in terms of rows execution
storage_filtered_rows		Rows removed by filter on storage layer
query_filtered_rows		Rows filtered in Query layer
storage_write_request	bigint	Total number of write request issued to storage layer
storage_read_request_time	double precision	Total time the statement spent in storage read request, in milliseconds (if track_io_timing is enabled, otherwise zero)	Should we break it for the main table and index table ??
storage_write_request_time	doubleprecision	Total time the statement spent in storage write request , in milliseconds (if track_io_timing is enabled, otherwise zero)
catalog_read_request	bigint	Total number of Catalog request
catalog_read_request_time	double precision	Total time the statement spent in catalog read request , in milliseconds (if track_io_timing is enabled, otherwise zero)
statement_retries	bigint	Number of times this statement is retried
Histogram	TBD
storage_next	bigint
storage_seek	bigint

[sushantrmishra]

statement retries is added via #15372