== baseline: persist a Product whose Map holds only JSON-native Java types (String, Integer, Double, Map, List)
sql> insert into product (attributes,dimensions,name,specs,tags) values (?,?,?,?,?)

== load, change nothing, commit
UPDATE statements: 0

== in-place mutations: load, mutate the object graph, commit, count UPDATEs
attributes.put("color", "blue")                                      -> 1 UPDATE
      update product set attributes=?,dimensions=?,name=?,specs=?,tags=? where id=?
attributes.remove("stock")                                           -> 1 UPDATE
      update product set attributes=?,dimensions=?,name=?,specs=?,tags=? where id=?
((Map) attributes.get("nested")).put("k2", 1)  [nested map]          -> 1 UPDATE
      update product set attributes=?,dimensions=?,name=?,specs=?,tags=? where id=?
((List) nested.get("k")).add(4)  [list inside map]                   -> 1 UPDATE
      update product set attributes=?,dimensions=?,name=?,specs=?,tags=? where id=?
tags.add("c")                                                        -> 1 UPDATE
      update product set attributes=?,dimensions=?,name=?,specs=?,tags=? where id=?
specs.setMaterial("brass")  [POJO setter]                            -> 1 UPDATE
      update product set attributes=?,dimensions=?,name=?,specs=?,tags=? where id=?
specs.getCertifications().add("UL")  [list inside POJO]              -> 1 UPDATE
      update product set attributes=?,dimensions=?,name=?,specs=?,tags=? where id=?
setDimensions(new Dimensions(9,9,9))  [record replaced]              -> 1 UPDATE
      update product set attributes=?,dimensions=?,name=?,specs=?,tags=? where id=?
setDimensions(equal record)  [no real change]                        -> 0 UPDATE

== the changes really reached the database
attributes = {"color": "blue", "price": 19.9, "nested": {"k": [1, 2, 3, 4], "k2": 1}}
tags       = ["a", "b", "c"]
specs      = {"material": "brass", "weightKg": 1.8, "certifications": ["CE", "UL"]}

== spurious UPDATEs: nothing changed, Hibernate writes anyway
persist() with attributes.price = new BigDecimal("19.90") -> 1 UPDATE right after the INSERT
   sql> insert into product (attributes,dimensions,name,specs,tags) values (?,?,?,?,?)
   sql> update product set attributes=?,dimensions=?,name=?,specs=?,tags=? where id=?
stored price after that persist: 19.90
then a plain load + commit of that row -> 0 UPDATE
load + commit of a row whose POJO has NO equals(), nothing touched -> 1 UPDATE
   sql> select l1_0.id,l1_0.specs from loose l1_0 where l1_0.id=?
   sql> update loose set specs=? where id=?
same for Specs, which HAS equals() (Product row, nothing touched) -> 0 UPDATE

== @DynamicUpdate: only the changed JSON column is written
sql> update dyn set a=? where id=?