EXECUTE IMMEDIATE 语句执行动态 SQL 语句或匿名 PL/SQL 块。您可以使用它来发出不能直接在 PL/SQL 中表示的 SQL 语句,或者在您事先不知道所有表名、WHERE 子句等的情况下构建语句

继续你的问题
-- Case using 1 output column 'COUNT(*)', 1 filter variable 'eb_key'
DECLARE
--
eb_key VARCHAR2(100) := 'something';
l_entry_found number;
--
BEGIN
execute immediate 'SELECT COUNT(*) FROM hera.hera_user@iam WHERE username = :eb_key;' USING eb_key INTO l_entry_found;
END;
-- Case using 2 output column 'COUNT(*)', 3 filter variable 'eb_key'
DECLARE
--
eb_column1 VARCHAR2(100) := 'something';
eb_column2 VARCHAR2(100) := 'something';
l_entry_found1 number;
l_entry_found2 number;
--
BEGIN
execute immediate 'SELECT column1, column2 FROM hera.hera_user@iam WHERE username = :eb_1 AND lastname = :eb_2;' USING eb_column1, eb_column2 INTO l_entry_found1,l_entry_found2;
END;