MVP - Database

[FletcherDares]

Phase 1:

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• Implement Create Table, Insert Into, Select w/ Condition: Fletcher/feat db create table #18
  • Tests for these: Testing for Database implementation #22
• Configure CI as a mandatory database step:
  • Cargo test CI: Configure CI for project #21
  • Cargo check CI: CI - Add step to run cargo check  #28
• Support ORDER BY : Feat: Add support for Order By column in Select statement. #27
• Support LIMIT / OFFSET: LIMIT / OFFSET with Select statements #24

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Phase 2:

• Support multiple WHERE conditions with SELECT statements.
  • Part 1: DB - Refactor WHERE conditions to support multiple #37
  • Part 2: AST - WHERE: remove Operand order dependence #38
  • Part 3: DB - Implement WHERE evaluation for IS and IN #39
  • Part 4: DB - Evaluate WHERE stack #41
• Support DELETE statements: DB - DELETE statement implementation #42
• Support UPDATE statements
  • Part 1: AST - UPDATE statements supporting ORDER BY and LIMIT / OFFSET #43
  • Part 2: DB - UPDATE statement implementation #44

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Phase 3 - Improvements

• Integration tests: Interpreter - Integration tests & refactor #46
• Proper Error types:
  • DB - Improve Error messages to include line numbers. #53
  • Improve messages by getting entire SQL statement with execution errors, currently a blank line.
• WHERE clause Short Circuiting: DB - WHERE Clause Short-Circuiting #61
• Table Improvements
  • DROP TABLE functionality
    • AST / DB - CREATE implement IF NOT EXISTS #55
  • ALTER TABLE functionality
    • DB / AST - ALTER TABLE implementation  #58
  • Database Transactions (Supported with actual diff tracking): Closed with MVP - Database Transactions #63
• SELECT Improvements
  • Return columns with the result rows
  • UNION, INTERSECT, EXCEPT functions
    • INITAL DONE: DB - SELECT Set Operators Initial Implementation #52
    • Implement Order By and Limit clauses: DB - SELECT set operators ORDER BY & LIMIT clauses #54
    • Refactor SelectStatement to no longer have a columns field
  • DISTINCT
    • DB / AST - DISTINCT with SELECT statement #59
  • Aggregate functions (COUNT, SUM, AVG, MIN, MAX)
  • GROUP BY
  • INNER JOIN
  • CROSS JOIN
  • RIGHT JOIN, LEFT JOIN, etc.

Bugs

• SELECT 1; is broken
• SELECT 1+1 FROM table; causes infinite loop that crashes.
• Have a way to load a demo db from CLI
• Add integration tests for SELECT 1 FROM table;, SELECT 1,2,3 FROM table;, SELECT 'alice' FROM table;
• Multiple Errors with this statement SELECT id, 5 FROM demo WHERE name='alice' OR name='bob' UNION ALL SELECT id, 5 FROM demo ORDER BY name DESC;
• Fix bug with HexLiterals being represented as Blobs in code incorrectly. Rename String, True and False -> StringLiteral, TrueLiteral and FalseLiteral DB - Fix bug with HexLiterals being Blobs #74