Feature Request: SQLSCRIPT - Dynamic Type Naming

[DMCTowns]

There are scenarios where being able to set the Type name in a query dynamically would be useful. For example:

LET sources = SELECT FROM Sources WHERE id='abc';
IF($sources.size() > 0){ 
  LET source = $sources[0];
  LET type = $source.type;
  LET target = SELECT FROM $type WHERE id='abc';
  CREATE EDGE IS_SOURCED_FROM FROM $target TO $source IF NOT EXISTS;
};

Currently, this isn't supported and would lead to the error on line 5:

Type with name '$type' was not found

[gramian]

A related missing feature in the above code is also that CREATE EDGE $edgetype FROM $source TO $ target does not allow variable (string) edge-type names.

[robfrank]

Actual supported variables:

        BEGIN;
        LET sources = SELECT FROM V1 WHERE id = '1';
        LET source = $sources[0];
        LET type = $source.vType;
        LET target = SELECT FROM $type WHERE id = '9';
        LET edgeType = 'HasSource';
        LET e = CREATE EDGE $edgeType FROM $target TO $source IF NOT EXISTS ;
        COMMIT;
        RETURN $e;

more tests needed to discover corners cases to be supported

[robfrank]

some notes on how to write scripts with dynamic type definitions: this works:

    LET docType = 'TheDoc';
    LET d =INSERT INTO $docType SET id = 1;

this doesn't work:

    LET docType = 'TheDoc';
    INSERT INTO $docType SET id = 1;

This is due to how the plan is create and executed. In the second example the INSERT... is executed immediately , not waiting for the execution of the LET statement before.

[robfrank]

new level unlocked:

        BEGIN;

        LET vTypes = ['V1', 'V2', 'V3'];
        FOREACH ($vType IN $vTypes) {
          CREATE VERTEX TYPE $vType EXTENDS V;
        }

        LET eTypes = ['E1', 'E2', 'E3'];
        FOREACH ($eType IN $eTypes) {
          CREATE EDGE TYPE  $eType EXTENDS E;
        }

        LET dTypes = ['D1', 'D2', 'D3'];
        FOREACH ($dType IN $dTypes) {
          CREATE DOCUMENT TYPE $dType ;
        }

        LET types = ['V1', 'V2', 'V3','E1', 'E2', 'E3','D1', 'D2', 'D3'];
        FOREACH ($type IN $types) {
          CREATE PROPERTY $type.id  STRING;
          CREATE INDEX ON $type (id) UNIQUE NULL_STRATEGY SKIP;
        }
        COMMIT;