What are the guidelines for joins?

What are the guidelines for joins?

- Join condition should ideally be written in the FROM clause.
- There should be no ambiguity in the column names to be joined.
- Depending on requirement, the type of JOIN should be chosen.
- To increase performance, one can limit the number of rows to be joined.
- Ideally, join tables with columns having same data type, width etc.
- Avoid joining tables with columns having few unique values.
What are the types of Join?
NON-EQUI Join, CARTESIAN Join, SELF Join, OUTER Join......
What a SELECT FOR UPDATE cursor represent?
The result of a PREPARE statement is a statement identifier. It is a data structure that represents the prepared statement text......
What WHERE CURRENT OF clause does in a cursor?
PL/SQL provides the WHERE CURRENT OF clause for both UPDATE and DELETE statements inside a cursor.....
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