diff options
Diffstat (limited to '')
| -rw-r--r-- | src/repl.erl | 49 |
1 files changed, 24 insertions, 25 deletions
diff --git a/src/repl.erl b/src/repl.erl index c61ebfe..599d721 100644 --- a/src/repl.erl +++ b/src/repl.erl @@ -21,30 +21,27 @@ %%% %%% == Query Syntax Examples == %%% <pre> -%%% % Scan relation -%%% {scan, employees} +%%% % Base relation (just use the name) +%%% employees %%% %%% % Filter -%%% {select, {scan, employees}, fun(T) -> maps:get(age, T) > 30 end} +%%% {select, employees, fun(T) -> maps:get(age, T) > 30 end} %%% %%% % Project -%%% {project, {scan, employees}, [name, age]} +%%% {project, employees, [name, age]} %%% %%% % Join -%%% {join, {scan, employees}, {scan, departments}, dept_id} +%%% {join, employees, departments, dept_id} %%% %%% % Rename -%%% {rename, age, years, {scan, employees}} +%%% {rename, age, years, employees} %%% %%% % Complex pipeline %%% {take, %%% {sort, %%% {project, %%% {select, -%%% {join, -%%% {scan, employees}, -%%% {scan, departments}, -%%% dept_id}, +%%% {join, employees, departments, dept_id}, %%% fun(T) -> maps:get(age, T) > 30 end}, %%% [name, dept_name, age]}, %%% fun(A, B) -> maps:get(age, A) =< maps:get(age, B) end}, @@ -79,7 +76,7 @@ %% @returns ok -spec start() -> ok. start() -> - operations:setup(), + main:setup(), io:format("~n~s~n", [banner()]), io:format("Domino REPL started. Type repl:help() for usage.~n~n"), ok. @@ -250,10 +247,10 @@ help() -> io:format("Quick Start:~n"), io:format(" repl:start(). %% Initialize system~n"), io:format(" DB = repl:example_db(). %% Create example database~n"), - io:format(" repl:q(DB, {scan, employees}). %% Run a query~n~n"), + io:format(" repl:q(DB, employees). %% Run a query~n~n"), io:format("Query Operators (all lazy by default):~n"), - io:format(" {scan, Name} - Scan relation~n"), + io:format(" RelationName - Base relation~n"), io:format(" {select, Plan, Predicate} - Filter tuples~n"), io:format(" {project, Plan, [Attrs]} - Project attributes~n"), io:format(" {join, Left, Right, Attr} - Equijoin~n"), @@ -281,39 +278,41 @@ help() -> io:format(" repl:modes() - List all available modes~n~n"), io:format("Examples:~n"), + io:format(" %% Query all employees~n"), + io:format(" repl:q(DB, employees).~n~n"), + io:format(" %% Filter employees over 30~n"), - io:format(" repl:q(DB, {select, {scan, employees}, ~n"), + io:format(" repl:q(DB, {select, employees, ~n"), io:format(" fun(T) -> maps:get(age, T) > 30 end}).~n~n"), io:format(" %% Project name and age~n"), - io:format(" repl:q(DB, {project, {scan, employees}, [name, age]}).~n~n"), + io:format(" repl:q(DB, {project, employees, [name, age]}).~n~n"), io:format(" %% Join employees with departments~n"), - io:format(" repl:q(DB, {join, {scan, employees}, ~n"), - io:format(" {scan, departments}, dept_id}).~n~n"), + io:format(" repl:q(DB, {join, employees, departments, dept_id}).~n~n"), io:format(" %% Rename age to years~n"), - io:format(" repl:q(DB, {rename, age, years, {scan, employees}}).~n~n"), + io:format(" repl:q(DB, {rename, age, years, employees}).~n~n"), io:format(" %% Materialize first 10 tuples (eager evaluation)~n"), - io:format(" repl:q(DB, {materialize, {scan, employees}, 10}).~n~n"), + io:format(" repl:q(DB, {materialize, employees, 10}).~n~n"), io:format(" %% Nested materialize - select from materialized data~n"), - io:format(" repl:q(DB, {select, {materialize, {scan, employees}},~n"), + io:format(" repl:q(DB, {select, {materialize, employees},~n"), io:format(" fun(T) -> maps:get(age, T) > 30 end}).~n~n"), io:format(" %% Use different visualization modes~n"), - io:format(" repl:q(DB, {scan, employees}, tree).~n"), - io:format(" repl:q(DB, {scan, employees}, nested_table).~n"), - io:format(" repl:q(DB, {scan, employees}, outline).~n~n"), + io:format(" repl:q(DB, employees, tree).~n"), + io:format(" repl:q(DB, employees, nested_table).~n"), + io:format(" repl:q(DB, employees, outline).~n~n"), io:format(" %% Query without printing, then show results~n"), - io:format(" Results = repl:query(DB, {scan, employees}).~n"), + io:format(" Results = repl:query(DB, employees).~n"), io:format(" Filtered = lists:filter(fun(T) -> maps:get(age, T) > 30 end, Results).~n"), io:format(" repl:show(Filtered, tree).~n~n"), io:format(" %% Explain a query plan~n"), - io:format(" repl:explain({select, {scan, employees}, ~n"), + io:format(" repl:explain({select, employees, ~n"), io:format(" fun(T) -> maps:get(age, T) > 30 end}).~n~n"), ok. |