oracle删除表，如果表不存在，就报错，在跑大型脚本（脚本长且耗时的时候）比较麻烦，一般希望的是点开始然后脚本运行到结束，不可能一直盯着屏幕等弹出提示手工点掉，mysql就很好有drop table if not exist功能
CREATE OR REPLACE PROCEDURE p_drop_table_if_exist(p_vc2_tbl_name IN all_tables.table_name%TYPE,
p_vc2_tbl_owner IN all_tables.owner%TYPE DEFAULT USER) IS
v_num_tbl_count NUMBER(4);
v_vc2_sql_stmt VARCHAR2(1000);
BEGIN
-- Check if table already exists
p_chk_table_exist(p_vc2_tbl_name, p_vc2_tbl_owner, v_num_tbl_count);
IF (v_num_tbl_count != 0) THEN
-- Table already exists and must be dropped
v_vc2_sql_stmt := "DROP TABLE " || CASE
WHEN p_vc2_tbl_owner IS NOT NULL THEN
p_vc2_tbl_owner || "."
END || p_vc2_tbl_name || " purge"
;
--dbms_output.put_line(v_vc2_sql_stmt);
EXECUTE IMMEDIATE v_vc2_sql_stmt;
END IF;
END;
CREATE OR REPLACE PROCEDURE p_chk_table_exist(p_vc2_tbl_name IN all_tables.table_name%TYPE,
p_vc2_tbl_owner IN all_tables.owner%TYPE DEFAULT USER,
p_num_tbl_count OUT NUMBER -- 1 if table exists, 0 if it doesn"t
) IS
v_vc2_tbl_name all_tables.table_name%TYPE := UPPER(p_vc2_tbl_name);
BEGIN
IF p_vc2_tbl_owner IS NOT NULL THEN
SELECT COUNT(1)
INTO p_num_tbl_count
FROM all_tables
WHERE table_name = v_vc2_tbl_name
AND owner = UPPER(p_vc2_tbl_owner);
ELSE
SELECT COUNT(1)
INTO p_num_tbl_count
FROM user_tables
WHERE table_name = v_vc2_tbl_name;
END IF;
END p_chk_table_exist;
have fun
