Use group by instead of distinct because distinct occupies more spool space
Use EXISTS instead of IN because EXISTS stops the process once it finds the value
Join Columns of same datatype
Use UNION ALL instead of UNION
Remove secondary indexes when the data is being loaded,updated or deleted
Avoid correlated queries,cross join, product join
use Delete ALL - normal delete have rollback, for delete all there is no rollback(no transient journal overhead)
Use EXISTS instead of IN because EXISTS stops the process once it finds the value
Join Columns of same datatype
Use UNION ALL instead of UNION
Remove secondary indexes when the data is being loaded,updated or deleted
Avoid correlated queries,cross join, product join
use Delete ALL - normal delete have rollback, for delete all there is no rollback(no transient journal overhead)
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