test: consistently analyze tables exactly once

Disabling the autovacuum daemon should also help reproducibility in
theory, although I don't know of any cases where we hit a problem with
that.

VACUUM changes the order of rows that PostgreSQL returns for some table
without explicit ordering, thus doing the latter to make it consistently
reproducible.

After ANALYZE estimates are 100% exact for the moment, so some requests
which returned 206 Partial Response now return 200 instead. The fact
that PostgREST returns 206 on an unfiltered endpoint can probably be
considered a bug.

test/spec/Feature/Query/PlanSpec.hs

@@ -15,12 +15,11 @@ import           Test.Hspec           hiding (pendingWith)
 import           Test.Hspec.Wai
 import           Test.Hspec.Wai.JSON
 
-import PostgREST.Config.PgVersion (PgVersion, pgVersion170)
-import Protolude                  hiding (get)
+import Protolude  hiding (get)
 import SpecHelper
 
-spec :: PgVersion -> SpecWith ((), Application)
-spec actualPgVersion = do
+spec :: SpecWith ((), Application)
+spec = do
   describe "read table/view plan" $ do
     it "outputs the total cost for a single filter on a table" $ do
       r <- request methodGet "/projects?id=in.(1,2,3)"
@@ -34,7 +33,7 @@ spec actualPgVersion = do
         resHeaders `shouldSatisfy` elem ("Content-Type", "application/vnd.pgrst.plan+json; for=\"application/json\"; charset=utf-8")
         resHeaders `shouldSatisfy` notZeroContentLength
         resStatus `shouldBe` Status { statusCode = 200, statusMessage="OK" }
-        totalCost `shouldBe` (if actualPgVersion >= pgVersion170 then 11.32 else 15.63)
+        totalCost `shouldBe` 1.11
 
     it "outputs the total cost for a single filter on a view" $ do
       r <- request methodGet "/projects_view?id=gt.2"
@@ -47,7 +46,7 @@ spec actualPgVersion = do
       liftIO $ do
         resHeaders `shouldSatisfy` elem ("Content-Type", "application/vnd.pgrst.plan+json; for=\"application/json\"; charset=utf-8")
         resStatus `shouldBe` Status { statusCode = 200, statusMessage="OK" }
-        totalCost `shouldBe` 24.28
+        totalCost `shouldBe` 1.1
 
     it "outputs blocks info when using the buffers option" $ do
       r <- request methodGet "/projects" (acceptHdrs "application/vnd.pgrst.plan+json; options=buffers") ""
@@ -143,7 +142,7 @@ spec actualPgVersion = do
         resHeaders `shouldSatisfy` elem ("Content-Type", "application/vnd.pgrst.plan+json; for=\"application/json\"; charset=utf-8")
         resHeaders `shouldSatisfy` notZeroContentLength
         resStatus `shouldBe` Status { statusCode = 200, statusMessage="OK" }
-        totalCost `shouldBe` 8.23
+        totalCost `shouldBe` 1.13
 
     it "outputs the total cost for a delete" $ do
       r <- request methodDelete "/projects?id=in.(1,2,3)"
@@ -157,7 +156,7 @@ spec actualPgVersion = do
         resHeaders `shouldSatisfy` elem ("Content-Type", "application/vnd.pgrst.plan+json; for=\"application/json\"; charset=utf-8")
         resHeaders `shouldSatisfy` notZeroContentLength
         resStatus `shouldBe` Status { statusCode = 200, statusMessage="OK" }
-        totalCost `shouldBe` (if actualPgVersion >= pgVersion170 then 11.37 else 15.68)
+        totalCost `shouldBe` 1.16
 
     it "outputs the total cost for a single upsert" $ do
       r <- request methodPut "/tiobe_pls?name=eq.Go"
@@ -490,7 +489,7 @@ spec actualPgVersion = do
 
         liftIO $ do
           resHeaders `shouldSatisfy` elem ("Content-Type", "application/vnd.pgrst.plan+json; for=\"application/json\"; options=analyze; charset=utf-8")
-          totalCost `shouldSatisfy` (> 49.0)
+          totalCost `shouldSatisfy` (> 2.0)
           aggregateQty `shouldSatisfy` (> 1)
 
     context "functions with count=exact" $ do