sql - Finding the hash value of a row in postgresql -

is there way hash code of row in postgresql?

i need export data if there changes in data after last export, last exported data rows can stored in table, when again need export data can hash values of data , export rows has different hash value last export.

is possible achieve using postgresql?

thank you

cast row text , use md5 make hash:

select     md5(cast((f.*)as text))     foo f;