Oracle 18c

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CREATE TABLE class_men ( regTime, sdudent_type ) AS
SELECT DATE '2021-01-01' + INTERVAL '1' MINUTE * LEVEL, 'AAAA1'
  FROM DUAL CONNECT BY LEVEL <= 250 UNION ALL
SELECT DATE '2021-01-01' + INTERVAL '1' MINUTE * LEVEL, 'AAAA2'
  FROM DUAL CONNECT BY LEVEL <= 42 UNION ALL
SELECT DATE '2021-01-01' + INTERVAL '1' MINUTE * LEVEL, 'AAAA3'
  FROM DUAL CONNECT BY LEVEL <= 13 UNION ALL
SELECT DATE '2021-01-02' + INTERVAL '1' MINUTE * LEVEL, 'AAAA1'
  FROM DUAL CONNECT BY LEVEL <= 99 UNION ALL
SELECT DATE '2021-01-02' + INTERVAL '1' MINUTE * LEVEL, 'AAAA2'
  FROM DUAL CONNECT BY LEVEL <= 17 UNION ALL
SELECT DATE '2021-01-02' + INTERVAL '1' MINUTE * LEVEL, 'AAAA3'
  FROM DUAL CONNECT BY LEVEL <= 24 UNION ALL
SELECT DATE '2021-01-03' + INTERVAL '1' MINUTE * LEVEL, 'AAAA1'
  FROM DUAL CONNECT BY LEVEL <= 23 UNION ALL
SELECT DATE '2021-01-03' + INTERVAL '1' MINUTE * LEVEL, 'AAAA3'
  FROM DUAL CONNECT BY LEVEL <= 50;
518 rows affected

ALTER SESSION SET NLS_DATE_FORMAT = 'YYYY-MM-DD HH24:MI:SS';
SELECT TRUNC( RegTime ) AS RegTime,                         
       COUNT(CASE WHEN sdudent_type = 'AAAA1' THEN 1 END) AS T8,
       COUNT(CASE WHEN sdudent_type = 'AAAA2' THEN 1 END) AS T9,
       COUNT(CASE WHEN sdudent_type = 'AAAA3' THEN 1 END) AS T10                   
FROM   class_men C
WHERE  REGTIME >= TO_DATE( '20210101000000','YYYYMMDDHH24MISS')
AND    REGTIME < TO_DATE( '20210104000000','YYYYMMDDHH24MISS')
GROUP BY TRUNC( RegTime );


REGTIME
T8
T9
T10


2021-01-01 00:00:00
250
42
13

2021-01-03 00:00:00
23
0
50

2021-01-02 00:00:00
99
17
24

REGTIME	T8	T9	T10
2021-01-01 00:00:00	250	42	13
2021-01-03 00:00:00	23	0	50
2021-01-02 00:00:00	99	17	24