If I execute INSERT OVERWRITE TABLEA statement and it takes 5 minutes to run. During its execution if I run SELECT * FROM TABLEA is there any possibility that I will not see any data? because of INSERT OVERWRITE first truncate the data and then load it.
I experienced that the data was not there in TABLEA but after the pipeline run it i saw the data
The default isolation level in Snowflake is Read Committed; which means you can't read uncommitted data. The Transaction you are running is INSERT OVERWRITE which works similarly to Truncate and load; the data is seen only when the transaction is complete. The command to view the default isolation level in Snowflake is
SHOW PARAMETERS LIKE 'TRANSACTION_DEFAULT_ISOLATION_LEVEL' IN ACCOUNT;