sql - difference between null and 0 while counting rows -


i have query follows

select owner, table_name,num_rows all_tables

for of tables num_rows 0 of table num_rows showing null

i'm not getting difference between these two.

on condition null come , when 0 displayed?

thank

i think null showing on tables without statistics. last_analyzed should null too. try query last_analyzed , check it.

select owner, table_name,num_rows, last_analyzed  all_tables;

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