specify child table name instead using ID in tag field.

user pass timestamp precision for line protocol, openTSDB related
timestamp accpet only 10 digits(second) or 13 digits(millisecond) by
default

length(<=64) boundaries.

JSON numbers.
Interger number -> BIGINT (contains only digits and '+' '-')
Floating number -> DOUBLE (including decimal point format or scientific
notation format)