A positive number added to another positive number always results in a positive number.
Understanding the (+) Symbol
The (+) symbol represents a positive number or value. In mathematics, it signifies that a quantity is greater than zero. This is fundamental to arithmetic operations. The references provided touch upon the (+) symbol in the context of Oracle SQL joins, but its core meaning remains consistent across various contexts. In the simplest mathematical sense, it indicates a positive value.
Mathematical Operations with Positive Numbers
- Addition: (+) + (+) = + This means adding two positive numbers always yields a positive sum. For example: 5 + 3 = 8.
- Subtraction: While not directly asked, it's relevant to note that subtracting a smaller positive number from a larger positive number will result in a positive difference. For example: 7 - 2 = 5. If the order is reversed, resulting in a negative difference: 2-7 = -5
Oracle SQL Context (As Seen in References)
Several references discuss the (+) symbol within the context of Oracle SQL queries. In this specific database environment, (+) signifies an outer join. This is not the same as the mathematical addition mentioned above. In SQL, this operator is used to specify how tables are joined, and it indicates that all rows from one table will be included in the result, even if they don't have a matching row in the other table.
Examples in Different Contexts
- Mathematical context: 10 (+) + 5 (+) = 15 (+)
- Oracle SQL context (Outer Join):
SELECT * FROM table1 t1, table2 t2 WHERE t1.id (+) = t2.id;This would perform a right outer join ( all rows from table2, even if not present in table 1)
