69 lines
3.9 KiB
Haskell
69 lines
3.9 KiB
Haskell
{-# LANGUAGE PatternSynonyms #-}
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module NormalizationSpec (spec) where
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import ChuSQL.Core.Engine.Normalization
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import ChuSQL.Core.Model (pattern TInt)
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import Test.Hspec
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-- 范式分析回归：公理闭包、候选键、信息不足与分解性质。
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-- 执行范式检查回归。
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spec :: Spec
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spec = do
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describe "Armstrong normalization" $ do
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it "computes reflexivity, augmentation and transitivity" $ do
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attributeClosure [Dependency ["a"] ["b"], Dependency ["b"] ["c"]] ["a"]
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`shouldBe` ["a", "b", "c"]
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implies [Dependency ["a"] ["b"]] (Dependency ["a", "c"] ["b", "c"])
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`shouldBe` True
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attributeClosure [] ["a"] `shouldBe` ["a"]
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it "accepts BCNF with a declared key" $ do
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fmap (map verdict . findings) (analyzeNormalization schema
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(Declaration [["a"]] [] True (Just True)))
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`shouldBe` Right (replicate 4 Satisfied)
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it "detects partial dependencies of composite keys" $ do
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fmap (map verdict . findings) (analyzeNormalization schema
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(Declaration [["a", "b"]] [Dependency ["a"] ["c"]] True (Just True)))
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`shouldBe` Right [Satisfied, Violated, Violated, Violated]
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it "detects transitive dependencies and a preserving split" $ do
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let analysis = analyzeNormalization schema
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(Declaration [["a"]] [Dependency ["b"] ["c"]] True (Just True))
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fmap (map verdict . findings) analysis
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`shouldBe` Right [Satisfied, Satisfied, Violated, Violated]
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fmap suggestions analysis
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`shouldBe` Right [Decomposition [["b", "c"], ["a", "b"]] Satisfied Satisfied]
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it "distinguishes 3NF from BCNF and detects dependency loss" $ do
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let analysis = analyzeNormalization schema
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(Declaration [["a", "b"]] [Dependency ["c"] ["b"]] True (Just True))
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fmap (map verdict . findings) analysis
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`shouldBe` Right [Satisfied, Satisfied, Satisfied, Violated]
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fmap suggestions analysis
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`shouldBe` Right [Decomposition [["b", "c"], ["a", "c"]] Satisfied Violated]
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it "does not certify incomplete dependencies" $ do
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fmap (map verdict . findings) (analyzeNormalization schema
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(Declaration [["a"]] [] False (Just True)))
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`shouldBe` Right [Satisfied, Insufficient, Insufficient, Insufficient]
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it "requires an atomicity declaration" $ do
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fmap (map verdict . findings) (analyzeNormalization schema
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(Declaration [] [] True Nothing)) `shouldBe` Right (replicate 4 Insufficient)
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it "propagates a declared 1NF violation" $ do
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fmap (map verdict . findings) (analyzeNormalization schema
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(Declaration [] [] True (Just False))) `shouldBe` Right (replicate 4 Violated)
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it "rejects unknown attributes" $ do
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analyzeNormalization schema (Declaration [] [Dependency ["z"] ["a"]] True (Just True))
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`shouldBe` Left "normalization: unknown or duplicate dependency attributes"
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it "rejects nonminimal declared candidate keys" $ do
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analyzeNormalization schema (Declaration [["a", "b"]]
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[Dependency ["a"] ["b", "c"]] True (Just True))
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`shouldBe` Left "normalization: declared candidate key is not minimal"
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it "includes the empty candidate key for constant relations" $ do
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fmap candidateKeys (analyzeNormalization schema
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(Declaration [] [Dependency [] ["a", "b", "c"]] True (Just True))) `shouldBe` Right [[]]
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it "rejects excessive exhaustive searches" $ do
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analyzeNormalization [(show n, TInt) | n <- [1 :: Int .. 13]]
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(Declaration [] [] True (Just True))
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`shouldBe` Left "normalization: exhaustive analysis supports at most 12 columns"
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where
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schema = [("a", TInt), ("b", TInt), ("c", TInt)]
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