以下为测试场景，实际业务并非如此，但效果一样
临时表：

CREATE GLOBAL TEMPORARY TABLE "TMP_GET_INTERESTRATE_EXT_SEG"
(
"BEG_DATE" CHAR(10),
"END_DATE" CHAR(10),
"RATE_VALUE" NUMBER(32,16),
"FLAG" NUMBER(38,0))
ON COMMIT PRESERVE ROWS STORAGE(ON TEMP);

函数：

CREATE OR REPLACE FUNCTION TEST() RETURN NUMBER AS
        PRAGMA AUTONOMOUS_TRANSACTION;

    BEGIN
	
        DELETE FROM TMP_GET_INTERESTRATE_EXT_SEG;
        COMMIT;
		FOR I IN 1 .. 100 LOOP
		   INSERT INTO TMP_GET_INTERESTRATE_EXT_SEG
                    (beg_date, end_date, rate_value, flag)
                VALUES
                    ('2019-09-01', '2020-08-09', I, 0);
		END LOOP;
        DELETE FROM TMP_GET_INTERESTRATE_EXT_SEG;
        COMMIT;

        RETURN 1;
    END;

执行语句：

BEGIN
  --调试语句
  FOR I IN 1 .. 10000 LOOP
   select TEST() into j from dual;
  END LOOP;
END;

循环10000

耗时1分25秒
循环50000

15分钟了还没执行完

函数改一下就行了，把delete语句改成一个清除数据的函数，SYSDBA是模式名，换成临时表所在的模式名即可

CREATE OR REPLACE FUNCTION TEST() RETURN NUMBER AS
        PRAGMA AUTONOMOUS_TRANSACTION;

    BEGIN
	    sp_tmp_table_clear('SYSDBA','TMP_GET_INTERESTRATE_EXT_SEG');
        --DELETE FROM TMP_GET_INTERESTRATE_EXT_SEG;
        COMMIT;
		FOR I IN 1 .. 100 LOOP
		   INSERT INTO TMP_GET_INTERESTRATE_EXT_SEG
                    (beg_date, end_date, rate_value, flag)
                VALUES
                    ('2019-09-01', '2020-08-09', I, 0);
		END LOOP;
        sp_tmp_table_clear('SYSDBA','TMP_GET_INTERESTRATE_EXT_SEG');
       -- DELETE FROM TMP_GET_INTERESTRATE_EXT_SEG;
        COMMIT;

        RETURN 1;
    END;

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