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sys.row_number_from_rowid
Return the row number for a row (starting from 0). Row numbers are relative values that are unique to a given combination of worker, SSD, and shard.
sys.row_number_from_rowid(rowid)
This function accepts either the string rowid
as its input or a specific rowid
value. In most cases you will use the string rowid
to return the specific row ID for each row in a set of rows. (If you specify an individual row ID as the input to the function, make sure it is valid; the system does not detect row IDs that are not valid or do not exist.)
For example:
yellowbrick_test=# select sys.worker_id_from_rowid(rowid) worker,
sys.filesys_number_from_rowid(rowid) ssd,
sys.inode_number_from_rowid(rowid) shard,
sys.row_number_from_rowid(rowid) rownum
from matchstats order by 1 limit 10;
worker | ssd | shard | rownum
--------+-----+--------+--------
0 | 7 | 168961 | 338055
0 | 7 | 168961 | 338056
0 | 7 | 168961 | 338057
0 | 7 | 168961 | 338058
0 | 7 | 168961 | 338059
0 | 7 | 168961 | 338060
0 | 7 | 168961 | 338061
0 | 7 | 168961 | 338062
0 | 7 | 168961 | 338063
0 | 7 | 168961 | 338064
(10 rows)
Parent topic:System Functions