diff --git a/src/backend/db/db.sql b/src/backend/db/db.sql
index 6d6be3ca..189b2012 100644
--- a/src/backend/db/db.sql
+++ b/src/backend/db/db.sql
@@ -157,7 +157,7 @@ CREATE TABLE Measurement (
 
   values float4[] NOT NULL,
 
-  primary key (invocation, runId, trialId, criterion),
+  primary key (runId, trialId, criterion, invocation),
   foreign key (trialId) references Trial (id),
   foreign key (runId) references Run (id),
   foreign key (criterion) references Criterion (id)
@@ -171,7 +171,7 @@ CREATE TABLE ProfileData (
 
   value text NOT NULL,
 
-  primary key (numIterations, invocation, runId, trialId),
+  primary key (runId, trialId, numIterations, invocation),
   foreign key (trialId) references Trial (id),
   foreign key (runId) references Run (id)
 );
diff --git a/src/backend/db/schema-updates/migration.015.sql b/src/backend/db/schema-updates/migration.015.sql
new file mode 100644
index 00000000..78fb2368
--- /dev/null
+++ b/src/backend/db/schema-updates/migration.015.sql
@@ -0,0 +1,9 @@
+-- The PK is wrongly ordered and makes queries for getting measurements very slow
+-- because we end up scanning through all of the table.
+ALTER TABLE Measurement 
+  DROP CONSTRAINT measurement_pkey,
+  ADD CONSTRAINT measurement_pkey PRIMARY KEY (runid, trialid, criterion, invocation);
+
+ALTER TABLE ProfileData
+  DROP CONSTRAINT profiledata_pkey,
+  ADD CONSTRAINT profiledata_pkey PRIMARY KEY (runid, trialid, numiterations, invocation);