Feat: Support check constraint

[huydo862003]

Summary

• dbml-parse:
  • Support constraint setting in table columns and tablepartial columns: a column can have multiple constraints.

        Table User {
              balance int [constraint: `balance > 0`, constraint: `balance < 100000000`]
        }
    

  • Support constraints element in table and tablepartial elements: A table can contain multiple constraints and a constraint can be named or nameless.

       Table User {
              balance int
              constraints {
                  `balance >= 0` [name: "balance_not_negative"]
                  `balance < 1000000000`
              }
       }
    

  • Constraints in TablePartial will be injected into the Table that injects the partial. Constraint names injected this way will be modified properly to avoid duplicate constraint names.
  • Support autocompletion related to constraints and constraint.
    • When inside a column setting, constraint would be suggested.
    • When inside a Table element, constraints would be suggested.
    • When inside a constraint setting, name would be suggested.
  • Function expressions (`expr`) can now contain newlines to better support complex conditions. Example:

        Table inventory {
            stock int
            status string
            constraints {
               `CASE WHEN status = 'active' THEN stock
                           WHEN status = 'discontinued' THEN 0
                           ELSE 1
                 END >= 0`
            }
        }
    

  • Some minor bug fixes and refactors.
• dbml-core:
  • Support constraints in model structure.
  • Support constraints in all parsers & exporters.
    • Support column's check constraints.
    • Support table definition's check constraints.
    • Support ALTER TABLE ADD CONSTRAINT.
  • Remove CONSTRAINT as plsql_unreserved_keyword from Postgres ANTLR grammar.
  • No longer support converting CHECK constraints into DBML ENUMs in MSSQL parser.
• Not supported yet:
  • ALTER TABLE ALTER CONSTRAINT is not supported and is currently ignored when importing SQL.
  • ALTER TABLE DROP CONSTRAINT is not supported and is currently ignored when importing SQL.
  • ALTER TABLE RENAME CONSTRAINT is not supported.
  • Duplicate constraint names are allowed. We currently do not perform duplicate constraint names check.

Issue

#591
#484
#68

Lasting Changes (Technical)

(please list down: code changes/things that have wide-effect; new libraries/functions added that can be used by others; examples below)

• (Added class EmailValidator to validate email address' validity)
• (Added Tenant#is_trial? check)

Checklist

Please check directly on the box once each of these are done

• Documentation (if necessary)
• Tests (integration test/unit test)
• Integration Tests Passed
• Code Review

[huyphung1602]

LGTM

[NQPhuc]

Please remember to update docs under dbml-homepage as well.