Steps to reproduce:

1. Create an item with floating point type
2. Fill history data

   insert into history values (<itemid>, 1696672800,  10.5, 0);
   insert into history values (<itemid>, 1696672860,  8.33, 0);
   insert into history values (<itemid>, 1696672920, 12.69, 0);
   insert into history values (<itemid>, 1696672980, 4.025, 0);
   insert into history values (<itemid>, 1696673160,   3.1, 0);
   insert into history values (<itemid>, 1696673220,     7, 0);
   insert into history values (<itemid>, 1696673280,  6.66, 0);
   insert into history values (<itemid>, 1696673580,  -1.5, 0);
   insert into history values (<itemid>, 1696673640,  0.31, 0);
   insert into history values (<itemid>, 1696673700,  6.47, 0);
   insert into history values (<itemid>, 1696673760,  2.11, 0);
   insert into history values (<itemid>, 1696673820,  8.98, 0);
   insert into history values (<itemid>, 1696673880, 10.01, 0);

   <itemid> must be replaced with the id of the created item

3. Open a line graph with period 2023-10-07 12:58:00 - 2023-10-07 13:20:00 (In the Europe/Riga time zone)
4. Repeat this with another database (MySQL or PostgreSQL)

Result:
MySQL:

PostgreSQL:

Difference:

Expected:
Both graphs should be the same.