How to write a dynamic sql code in teradata?

@wilmer.lemke 

Dynamic SQL in Teradata can be written using the EXECUTE IMMEDIATE command. This allows you to build SQL statements dynamically based on certain conditions or parameters. Here is an example of how to write dynamic SQL in Teradata:

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REPLACE PROCEDURE dynamic_sql_example()
BEGIN

    DECLARE sql_stmt VARCHAR(1000);
    DECLARE var_id INTEGER;
    DECLARE var_name VARCHAR(50);

    SET var_id = 1;
    SET var_name = 'John';

    SET sql_stmt = 'SELECT * FROM employees WHERE ';

    IF var_id IS NOT NULL THEN
        SET sql_stmt = sql_stmt || 'employee_id = ' || var_id;
    END IF;

    IF var_name IS NOT NULL THEN
        IF var_id IS NOT NULL THEN
            SET sql_stmt = sql_stmt || ' AND ';
        END IF;
        SET sql_stmt = sql_stmt || 'employee_name = ''' || var_name || '''';
    END IF;

    EXECUTE IMMEDIATE sql_stmt;

END;

In this example, we are creating a stored procedure called dynamic_sql_example. We declare variables var_id and var_name to hold dynamic values. We then build a SQL statement based on the values of these variables using conditional logic. Finally, we execute the dynamically built SQL statement using the EXECUTE IMMEDIATE command.

Remember to use caution when using dynamic SQL as it can introduce security risks like SQL injection. Always validate and sanitize user inputs before building dynamic SQL statements.