Wrong result for count(*) in hive table

Question

I have created a table in HIVE

CREATE TABLE IF NOT EXISTS daily_firstseen_analysis (
    firstSeen         STRING,
    category          STRING,
    circle           


        

Answer 1

if you have an external table, remove all the files in HDFS, and insert into the table again then select count(*) will be incorrect.

Answer 2

I execute ANALYZE TABLE ... at first is OK, but raise error when i try again.so i try:

hive> REFRESH TABLE daily_firstseen_analysis;
hive> SELECT COUNT(*) FROM daily_firstseen_analysis;

this is explain

Answer 3

I had the same problem, and using ANALYZE fixed it. Running these commands in order should give you the correct count:

hive> ANALYZE TABLE daily_firstseen_analysis PARTITION(day) COMPUTE STATISTICS;
hive> SELECT COUNT(*) FROM daily_firstseen_analysis;

i.e. you have to use the analyze command before the count. You have half the answer within your question.