Wt

Adding a field flag which causes Wt::Dbo to generate "insert" and "update" statements with DEFAULT value to current field (database serverside).

For example if we have table like

create table Test_table (id int PRIMARY KEY, name text NOT NULL, quota int DEFAULT 100 NOT NULL, create_date DEFAULT now());

with using of Dbo::ptr cause to generating statements like

insert into "Test_table" ("id", "name", "quota", "create_date") values ($1, $2, $3, $4) returning "id" 
bind: $1 = default, $2 = 'qweqwe', $3 = deafult, $4 = default

detailed log of events:

LOG:  statement: start transaction
LOG:  duration: 0.229 ms
DEBUG:  parse SQL0x2b157f003113C398: insert into "Test_table" ("id", "name", "quota", "create_date") values ($1, $2, $3, $4) returning "id" 
LOG:  duration: 2.226 ms  parse SQL0x2b157f003113C398: insert into "Test_table" ("id", "name", "quota", "create_date") values ($1, $2, $3, $4) returning "id" 
DEBUG:  bind <unnamed> to SQL0x2b157f003113C398
LOG:  duration: 0.101 ms  bind SQL0x2b157f003113C398: insert into "Test_table" ("id", "name", "quota", "create_date") values ($1, $2, $3, $4) returning "id" 
DETAIL:  parameters: $1 = default, $2 = 'qweqwe', $3 = deafult, $4 = default
LOG:  execute SQL0x2b157f003113C398: insert into "Test_table" ("id", "name", "quota", "create_date") values ($1, $2, $3, $4) returning "id" 
DETAIL:  parameters: $1 = default, $2 = 'qweqwe', $3 = deafult, $4 = default
LOG:  duration: 1.829 ms
LOG:  statement: commit transaction

when "default" flag is ON for some fields, value of this fields must be ignored (for any types and any values) to prevent misunderstandings.

Same for generating "update" statement with use Dbo::ptr::modify()