github.com/matrixorigin/matrixone@v1.2.0/test/distributed/cases/function/func_datetime_datediff.test (about)

     1  SELECT DATEDIFF('2017-08-17','2017-08-17');
     2  SELECT DATEDIFF('2017-08-17','2017-08-08');
     3  SELECT DATEDIFF('2017-08-08','2017-08-17');
     4  
     5  SELECT DATEDIFF(NULL,'2017-08-17');
     6  SELECT DATEDIFF('2017-08-17',NULL);
     7  SELECT DATEDIFF(NULL, NULL);
     8  
     9  drop table if exists t1;
    10  create table t1(a INT,  b date);
    11  insert into t1 values(1, "2012-10-11");
    12  insert into t1 values(2, "2004-04-24");
    13  insert into t1 values(3, "2008-12-04");
    14  insert into t1 values(4, "2012-03-23");
    15  insert into t1 values(5, "2000-03-23");
    16  insert into t1 values(6, "2030-03-23");
    17  insert into t1 values(7, "2040-03-23");
    18  SELECT a, DATEDIFF('2022-10-9', b) from t1;
    19  drop table t1;
    20  
    21  drop table if exists t1;
    22  create table t1(a INT,  b date);
    23  insert into t1 values(1, "2012-10-11");
    24  insert into t1 values(2, "2004-04-24");
    25  insert into t1 values(3, "2008-12-04");
    26  insert into t1 values(4, "2012-03-23");
    27  insert into t1 values(5, "2000-03-23");
    28  insert into t1 values(6, "2030-03-23");
    29  insert into t1 values(7, "2040-03-23");
    30  SELECT a, DATEDIFF(b, '2022-10-9') from t1;
    31  drop table t1;
    32  
    33  drop table if exists t1;
    34  create table t1(a date,  b date);
    35  insert into t1 values('2022-10-9', "2012-10-11");
    36  insert into t1 values('2022-10-9', "2004-04-24");
    37  insert into t1 values('2022-10-9', "2008-12-04");
    38  insert into t1 values('2022-10-9', "2012-03-23");
    39  insert into t1 values('2022-10-9', "2000-03-23");
    40  insert into t1 values('2022-10-9', "2030-03-23");
    41  insert into t1 values('2022-10-9', "2040-03-23");
    42  SELECT a, b, DATEDIFF(a, b) from t1;
    43  drop table t1;
    44  
    45