This commit allows the LP consumer to correctly handle line protocol
writes that duplicate one or more fields or tags within a single line:
table v=2,bananas=42,v=3,platanos=24
▲ ▲
└───────┬──────┘
│
duplicate field "v"
This change implements the following logic when processing fields:
IF field is duplicated
IF all duplicate field values are of the same data type
use last occurrence ("last write wins")
ELSE
return an error
Any duplication of tags is rejected, and use of a field name as both a
field and a tag is remains forbidden (unchanged in this PR, a previously
agreed breaking change from TSM).
See https://github.com/influxdata/influxdb_iox/issues/4326 for context.
Andrew Lamb
Dom Dwyer
Andrew Lamb
Marco Neumann
Carol (Nichols || Goulding)
Raphael Taylor-Davies