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In SQL, parentheses are primarily used to group conditions and expressions together to make a logical expression. Parentheses can also be used to specify order of operations in complex queries with multiple operators.

Here are some ways to manage parentheses in SQL:

1. Use parentheses to group conditions or expressions together in the WHERE clause of a SELECT statement. For example, "SELECT * FROM table WHERE (condition1 AND condition2) OR condition3;"

2. Use parentheses to specify order of operations in complex queries. For example, "SELECT colA, colB, (colC * colD) AS result FROM table ORDER BY result DESC;"

3. Use parentheses to group subqueries. For example, "SELECT * FROM table WHERE column1 IN (SELECT column2 FROM table2 WHERE condition);"

4. Use parentheses when joining multiple tables. For example, "SELECT * FROM table1 INNER JOIN (table2 INNER JOIN table3 ON table2.colX = table3.colY) ON table1.colZ = table2.colA;"

It is important to note that proper use and placement of parentheses is essential for the correct execution of SQL queries.