Library
Module
Module type
Parameter
Class
Class type
Create user-defined aggregate and window functions.
Aggregate functions provide the step
function, which is called once per value being added to the aggregate, and the final
function is called once to return the final value.
To make a window function (requires SQLite3 3.25 or newer; on older versions a normal aggregate function is created), the additional inverse
function, which removes a value from the window, and value
, which can be called many times and returns the current computed value of the window, must both be included.
val create_fun0 :
?inverse:('a -> 'a) ->
?value:('a -> Data.t) ->
db ->
string ->
init:'a ->
step:('a -> 'a) ->
final:('a -> Data.t) ->
unit
create_fun0 ?inverse ?value db name ~init ~step ~final
registers the step and finalizer functions and optional inverse and value functions under name name
with database handle db
. This function has arity 0
.
val create_fun1 :
?inverse:('a -> Data.t -> 'a) ->
?value:('a -> Data.t) ->
db ->
string ->
init:'a ->
step:('a -> Data.t -> 'a) ->
final:('a -> Data.t) ->
unit
create_fun1 ?inverse ?value db name ~init ~step ~final
registers the step and finalizer functions and optional inverse and value functions under name name
with database handle db
. This function has arity 1
.
val create_fun2 :
?inverse:('a -> Data.t -> Data.t -> 'a) ->
?value:('a -> Data.t) ->
db ->
string ->
init:'a ->
step:('a -> Data.t -> Data.t -> 'a) ->
final:('a -> Data.t) ->
unit
create_fun2 ?inverse ?value db name ~init ~step ~final
registers the step and finalizer functions and optional inverse and value functions under name name
with database handle db
. This function has arity 2
.
val create_fun3 :
?inverse:('a -> Data.t -> Data.t -> Data.t -> 'a) ->
?value:('a -> Data.t) ->
db ->
string ->
init:'a ->
step:('a -> Data.t -> Data.t -> Data.t -> 'a) ->
final:('a -> Data.t) ->
unit
create_fun3 ?inverse ?value db name ~init ~step ~final
registers the step and finalizer functions and optional inverse and value functions under name name
with database handle db
. This function has arity 3
.
val create_funN :
?inverse:('a -> Data.t array -> 'a) ->
?value:('a -> Data.t) ->
db ->
string ->
init:'a ->
step:('a -> Data.t array -> 'a) ->
final:('a -> Data.t) ->
unit
create_funN ?inverse ?value db name ~init ~step ~final
registers the step and finalizer functions and optional inverse and value functions under name name
with database handle db
. This function has arity N
.