Summary

In this chapter, you learned

• How to perform single and multiple table SELECT statements.

• How to select all columns from a table using the asterisk (*) in a SELECT statement.

• How a row identifier (rowid) is used internally by the Oracle database to access a row.

• How to perform arithmetic in SQL statements.

• How to use addition and subtraction operators with dates.

• How to reference tables and columns using aliases.

• How to merge column output using the concatenation operator (||).

• How nulls are used to represent unknown values.

• How to display distinct rows using the DISTINCT operator.

• How to limit retrieval of rows using the WHERE clause.

• How to sort rows using the ORDER BY clause.

• How to perform inner, outer, and self joins using the SQL/86 and SQL/92 syntax. SQL/86 is used by Oracle8i and below. SQL/92 is used by Oracle9i and above.