声明变量并在查询oracle中使用它们

DECLARE
  v_employee_id NUMBER;
BEGIN
  -- Your code here
END;

-- 给变量赋值
v_employee_id := 100;

-- 或者在查询中直接赋值
SELECT employee_id INTO v_employee_id FROM employees WHERE name = 'John Doe';

-- 使用变量构建动态查询
EXECUTE IMMEDIATE 'SELECT * FROM employees WHERE employee_id = :employee_id' USING v_employee_id;

-- 或者在查询中使用变量作为条件
SELECT * FROM employees WHERE employee_id = v_employee_id;

DECLARE
  v_employee_id NUMBER;
  v_employee_name VARCHAR2(100);
BEGIN
  -- 给变量赋值
  v_employee_id := 100;

  -- 在查询中使用变量作为条件
  SELECT name INTO v_employee_name FROM employees WHERE employee_id = v_employee_id;

  -- 输出查询结果
  DBMS_OUTPUT.PUT_LINE('Employee name: ' || v_employee_name);
END;