cubicweb #1109558 schema migration order relies on backend not using the null_allowed argument to adbh.sql_change_col_type [resolved]

Sql server uses that argument, and painful things follow.

A first round of bugs involving the wrong computation of that argument have been fixed.

Remaining issue :

  1. change an attribute from String(required=False, maxlength=250) to String(required=True, maxlength=255)
  2. there is a call to sql_set_null_allowed(False) (expected), followed by a call to sql_change_col_type with null_allowed=True, because in the call, cardinality is '?1' (WTF?) and this results in NULL allowed in the table
done in3.9.0
load left0.000
closed by<not specified>