diff --git a/database/database.go b/database/database.go
index 3a31aca95c..be508aa2f5 100644
--- a/database/database.go
+++ b/database/database.go
@@ -28,8 +28,9 @@ type Datastore interface {
 	DeleteLayer(name string) error
 
 	// Vulnerability
-	// InsertVulnerabilities([]*Vulnerability)
-	// DeleteVulnerability(id string)
+	InsertVulnerabilities([]Vulnerability) error
+	// DeleteVulnerability(id string) error
+	FindVulnerability(namespaceName, name string) (Vulnerability, error)
 
 	// Notifications
 	// InsertNotifications([]Notification) error
diff --git a/database/models.go b/database/models.go
index 95e84542a6..a7bef10dfa 100644
--- a/database/models.go
+++ b/database/models.go
@@ -2,6 +2,7 @@ package database
 
 import "github.com/coreos/clair/utils/types"
 
+// ID is only meant to be used by database implementations and should never be used for anything else.
 type Model struct {
 	ID int
 }
@@ -46,8 +47,9 @@ type Vulnerability struct {
 	Description string
 	Link        string
 	Severity    types.Priority
-	// FixedIn     map[types.Version]Feature // <<-- WRONG.
-	Affects []FeatureVersion
+
+	FixedIn []FeatureVersion
+	//Affects []FeatureVersion
 
 	// For output purposes. Only make sense when the vulnerability
 	// is already about a specific Feature/FeatureVersion.
diff --git a/database/pgsql/feature.go b/database/pgsql/feature.go
index 33d81ab832..8414540b7a 100644
--- a/database/pgsql/feature.go
+++ b/database/pgsql/feature.go
@@ -1,6 +1,8 @@
 package pgsql
 
 import (
+	"database/sql"
+
 	"github.com/coreos/clair/database"
 	cerrors "github.com/coreos/clair/utils/errors"
 	"github.com/coreos/clair/utils/types"
@@ -54,6 +56,7 @@ func (pgSQL *pgSQL) insertFeatureVersion(featureVersion database.FeatureVersion)
 	if err != nil {
 		return 0, err
 	}
+	featureVersion.Feature.ID = featureID
 
 	// Begin transaction.
 	tx, err := pgSQL.Begin()
@@ -62,6 +65,15 @@ func (pgSQL *pgSQL) insertFeatureVersion(featureVersion database.FeatureVersion)
 		return 0, handleError("insertFeatureVersion.Begin()", err)
 	}
 
+	// Set transaction as SERIALIZABLE.
+	// This is how we ensure that the data in Vulnerability_Affects_FeatureVersion is always
+	// consistent.
+	_, err = tx.Exec(getQuery("set_tx_serializable"))
+	if err != nil {
+		tx.Rollback()
+		return 0, handleError("insertFeatureVersion.set_tx_serializable", err)
+	}
+
 	// Find or create FeatureVersion.
 	var newOrExisting string
 	err = tx.QueryRow(getQuery("soi_featureversion"), featureID, &featureVersion.Version).
@@ -77,20 +89,48 @@ func (pgSQL *pgSQL) insertFeatureVersion(featureVersion database.FeatureVersion)
 
 	// Link the new FeatureVersion with every vulnerabilities that affect it, by inserting in
 	// Vulnerability_Affects_FeatureVersion.
+	err = linkFeatureVersionToVulnerabilities(tx, featureVersion)
+	if err != nil {
+		// tx.Rollback() is done in linkFeatureVersionToVulnerabilities.
+		return 0, err
+	}
 
-	// Lock Vulnerability_FixedIn_Feature because we can't let it to be modified while we modify
-	// Vulnerability_Affects_FeatureVersion.
-	_, err = tx.Exec(getQuery("l_share_vulnerability_fixedin_feature"))
+	// Commit transaction.
+	err = tx.Commit()
 	if err != nil {
-		tx.Rollback()
-		return 0, handleError("l_share_vulnerability_fixedin_feature", err)
+		return 0, handleError("insertFeatureVersion.Commit()", err)
+	}
+
+	if pgSQL.cache != nil {
+		pgSQL.cache.Add("featureversion:"+featureVersion.Feature.Name+":"+
+			featureVersion.Version.String(), featureVersion.ID)
 	}
 
+	return featureVersion.ID, nil
+}
+
+// TODO(Quentin-M): Batch me
+func (pgSQL *pgSQL) insertFeatureVersions(featureVersions []database.FeatureVersion) ([]int, error) {
+	IDs := make([]int, 0, len(featureVersions))
+
+	for i := 0; i < len(featureVersions); i++ {
+		id, err := pgSQL.insertFeatureVersion(featureVersions[i])
+		if err != nil {
+			return IDs, err
+		}
+		IDs = append(IDs, id)
+	}
+
+	return IDs, nil
+}
+
+func linkFeatureVersionToVulnerabilities(tx *sql.Tx, featureVersion database.FeatureVersion) error {
 	// Select every vulnerability and the fixed version that affect this Feature.
-	rows, err := tx.Query(getQuery("s_vulnerability_fixedin_feature"), featureID)
+	// TODO(Quentin-M): LIMIT
+	rows, err := tx.Query(getQuery("s_vulnerability_fixedin_feature"), featureVersion.Feature.ID)
 	if err != nil {
 		tx.Rollback()
-		return 0, handleError("s_vulnerability_fixedin_feature", err)
+		return handleError("s_vulnerability_fixedin_feature", err)
 	}
 	defer rows.Close()
 
@@ -100,7 +140,7 @@ func (pgSQL *pgSQL) insertFeatureVersion(featureVersion database.FeatureVersion)
 		err := rows.Scan(&fixedInID, &vulnerabilityID, &fixedInVersion)
 		if err != nil {
 			tx.Rollback()
-			return 0, handleError("s_vulnerability_fixedin_feature.Scan()", err)
+			return handleError("s_vulnerability_fixedin_feature.Scan()", err)
 		}
 
 		if featureVersion.Version.Compare(fixedInVersion) < 0 {
@@ -111,40 +151,14 @@ func (pgSQL *pgSQL) insertFeatureVersion(featureVersion database.FeatureVersion)
 				featureVersion.ID, fixedInID)
 			if err != nil {
 				tx.Rollback()
-				return 0, handleError("i_vulnerability_affects_featureversion", err)
+				return handleError("i_vulnerability_affects_featureversion", err)
 			}
 		}
 	}
 	if err = rows.Err(); err != nil {
-		return 0, handleError("s_vulnerability_fixedin_feature.Rows()", err)
-	}
-
-	// Commit transaction.
-	err = tx.Commit()
-	if err != nil {
 		tx.Rollback()
-		return 0, handleError("insertFeatureVersion.Commit()", err)
-	}
-
-	if pgSQL.cache != nil {
-		pgSQL.cache.Add("featureversion:"+featureVersion.Feature.Name+":"+
-			featureVersion.Version.String(), featureVersion.ID)
+		return handleError("s_vulnerability_fixedin_feature.Rows()", err)
 	}
 
-	return featureVersion.ID, nil
-}
-
-// TODO(Quentin-M): Batch me
-func (pgSQL *pgSQL) insertFeatureVersions(featureVersions []database.FeatureVersion) ([]int, error) {
-	IDs := make([]int, 0, len(featureVersions))
-
-	for i := 0; i < len(featureVersions); i++ {
-		id, err := pgSQL.insertFeatureVersion(featureVersions[i])
-		if err != nil {
-			return IDs, err
-		}
-		IDs = append(IDs, id)
-	}
-
-	return IDs, nil
+	return nil
 }
diff --git a/database/pgsql/layer.go b/database/pgsql/layer.go
index d2f941f57a..645ce2f446 100644
--- a/database/pgsql/layer.go
+++ b/database/pgsql/layer.go
@@ -77,7 +77,7 @@ func (pgSQL *pgSQL) getLayerFeatureVersions(layerID int, idOnly bool) ([]databas
 
 	// Query
 	rows, err := pgSQL.Query(query, layerID)
-	if err != nil && err != sql.ErrNoRows {
+	if err != nil {
 		return featureVersions, handleError(query, err)
 	}
 	defer rows.Close()
@@ -201,14 +201,23 @@ func (pgSQL *pgSQL) InsertLayer(layer database.Layer) error {
 	if err != nil && err != cerrors.ErrNotFound {
 		return err
 	} else if err == nil {
+		if existingLayer.EngineVersion >= layer.EngineVersion {
+			// The layer exists and has an equal or higher engine verison, do nothing.
+			return nil
+		}
+
 		layer.ID = existingLayer.ID
 	}
 
-	// Begin transaction.
-	tx, err := pgSQL.Begin()
-	if err != nil {
-		tx.Rollback()
-		return handleError("InsertLayer.Begin()", err)
+	// Get parent ID.
+	var parentID zero.Int
+	if layer.Parent != nil {
+		if layer.Parent.ID == 0 {
+			log.Warning("Parent is expected to be retrieved from database when inserting a layer.")
+			return cerrors.NewBadRequestError("Parent is expected to be retrieved from database when inserting a layer.")
+		}
+
+		parentID = zero.IntFrom(int64(layer.Parent.ID))
 	}
 
 	// Find or insert namespace if provided.
@@ -216,7 +225,6 @@ func (pgSQL *pgSQL) InsertLayer(layer database.Layer) error {
 	if layer.Namespace != nil {
 		n, err := pgSQL.insertNamespace(*layer.Namespace)
 		if err != nil {
-			tx.Rollback()
 			return err
 		}
 		namespaceID = zero.IntFrom(int64(n))
@@ -227,18 +235,15 @@ func (pgSQL *pgSQL) InsertLayer(layer database.Layer) error {
 		}
 	}
 
+	// Begin transaction.
+	tx, err := pgSQL.Begin()
+	if err != nil {
+		tx.Rollback()
+		return handleError("InsertLayer.Begin()", err)
+	}
+
 	if layer.ID == 0 {
 		// Insert a new layer.
-		var parentID zero.Int
-		if layer.Parent != nil {
-			if layer.Parent.ID == 0 {
-				log.Warning("Parent is expected to be retrieved from database when inserting a layer.")
-				return cerrors.NewBadRequestError("Parent is expected to be retrieved from database when inserting a layer.")
-			}
-
-			parentID = zero.IntFrom(int64(layer.Parent.ID))
-		}
-
 		err = tx.QueryRow(getQuery("i_layer"), layer.Name, layer.EngineVersion, parentID, namespaceID).
 			Scan(&layer.ID)
 		if err != nil {
@@ -246,11 +251,6 @@ func (pgSQL *pgSQL) InsertLayer(layer database.Layer) error {
 			return handleError("i_layer", err)
 		}
 	} else {
-		if existingLayer.EngineVersion >= layer.EngineVersion {
-			// The layer exists and has an equal or higher engine verison, do nothing.
-			return nil
-		}
-
 		// Update an existing layer.
 		_, err = tx.Exec(getQuery("u_layer"), layer.ID, layer.EngineVersion, namespaceID)
 		if err != nil {
@@ -269,6 +269,7 @@ func (pgSQL *pgSQL) InsertLayer(layer database.Layer) error {
 	// Update Layer_diff_FeatureVersion now.
 	err = pgSQL.updateDiffFeatureVersions(tx, &layer, &existingLayer)
 	if err != nil {
+		tx.Rollback()
 		return err
 	}
 
@@ -293,7 +294,7 @@ func (pgSQL *pgSQL) updateDiffFeatureVersions(tx *sql.Tx, layer, existingLayer *
 	} else if layer.Parent != nil {
 		// There is a parent, we need to diff the Features with it.
 
-		// Build name:version strctures.
+		// Build name:version structures.
 		layerFeaturesMapNV, layerFeaturesNV := createNV(layer.Features)
 		parentLayerFeaturesMapNV, parentLayerFeaturesNV := createNV(layer.Parent.Features)
 
diff --git a/database/pgsql/migrations/20151222113213_Initial.sql b/database/pgsql/migrations/20151222113213_Initial.sql
index 14f3092a7a..bdf8e9f8a1 100644
--- a/database/pgsql/migrations/20151222113213_Initial.sql
+++ b/database/pgsql/migrations/20151222113213_Initial.sql
@@ -73,7 +73,7 @@ CREATE TABLE IF NOT EXISTS Vulnerability (
   name VARCHAR(128) NOT NULL,
   description TEXT NULL,
   link VARCHAR(128) NULL,
-  severity severity NULL,
+  severity severity NOT NULL,
 
   UNIQUE (namespace_id, name));
 
@@ -137,6 +137,6 @@ DROP TABLE IF EXISTS Namespace,
                      Vulnerability,
                      Vulnerability_FixedIn_Feature,
                      Vulnerability_Affects_FeatureVersion,
-                     KeyValue
+                     KeyValue,
                      Lock
             CASCADE;
diff --git a/database/pgsql/pgsql.go b/database/pgsql/pgsql.go
index 476eca0f8e..d0ff887e7e 100644
--- a/database/pgsql/pgsql.go
+++ b/database/pgsql/pgsql.go
@@ -120,7 +120,7 @@ func dropDatabase(dataSource, databaseName string) error {
 	// Drop database.
 	_, err = db.Exec("DROP DATABASE " + databaseName + ";")
 	if err != nil {
-		return fmt.Errorf("could not create database: %v", err)
+		return fmt.Errorf("could not drop database: %v", err)
 	}
 
 	return nil
@@ -185,7 +185,7 @@ func handleError(desc string, err error) error {
 		return database.ErrBackendException
 	} else if err == sql.ErrNoRows {
 		return cerrors.ErrNotFound
-	} else if err == sql.ErrTxDone {
+	} else if err == sql.ErrTxDone || strings.HasPrefix(err.Error(), "sql:") {
 		return database.ErrBackendException
 	}
 
diff --git a/database/pgsql/queries.go b/database/pgsql/queries.go
index 112813a8a5..e108876557 100644
--- a/database/pgsql/queries.go
+++ b/database/pgsql/queries.go
@@ -10,6 +10,8 @@ var queries map[string]string
 func init() {
 	queries = make(map[string]string)
 
+	queries["set_tx_serializable"] = `SET TRANSACTION ISOLATION LEVEL SERIALIZABLE`
+
 	// keyvalue.go
 	queries["u_keyvalue"] = `UPDATE KeyValue SET value = $1 WHERE key = $2`
 	queries["i_keyvalue"] = `INSERT INTO KeyValue(key, value) VALUES($1, $2)`
@@ -39,10 +41,6 @@ func init() {
     UNION
     SELECT id FROM new_feature`
 
-	queries["l_share_vulnerability_fixedin_feature"] = `
-    LOCK Vulnerability_FixedIn_Feature IN SHARE MODE
-  `
-
 	queries["soi_featureversion"] = `
     WITH new_featureversion AS (
       INSERT INTO FeatureVersion(feature_id, version)
@@ -142,6 +140,41 @@ func init() {
 	queries["r_lock"] = `DELETE FROM Lock WHERE name = $1 AND owner = $2`
 
 	queries["r_lock_expired"] = `DELETE FROM LOCK WHERE until < CURRENT_TIMESTAMP`
+
+	// vulnerability.go
+	queries["f_vulnerability"] = `
+    SELECT v.id, n.id, v.description, v.link, v.severity, vfif.version, f.id, f.Name
+    FROM Vulnerability v
+      JOIN Namespace n ON v.namespace_id = n.id
+      LEFT JOIN Vulnerability_FixedIn_Feature vfif ON v.id = vfif.vulnerability_id
+      LEFT JOIN Feature f ON vfif.feature_id = f.id
+    WHERE n.Name = $1 AND v.Name = $2`
+
+	queries["i_vulnerability"] = `
+    INSERT INTO Vulnerability(namespace_id, name, description, link, severity)
+    VALUES($1, $2, $3, $4, $5)
+    RETURNING id`
+
+	queries["u_vulnerability"] = `
+    UPDATE Vulnerability SET description = $2, link = $3, severity = $4 WHERE id = $1`
+
+	queries["i_vulnerability_fixedin_feature"] = `
+    INSERT INTO Vulnerability_FixedIn_Feature(vulnerability_id, feature_id, version)
+    VALUES($1, $2, $3)
+    RETURNING id`
+
+	queries["u_vulnerability_fixedin_feature"] = `
+    UPDATE Vulnerability_FixedIn_Feature
+    SET version = $3
+    WHERE vulnerability_id = $1 AND feature_id = $2
+    RETURNING id`
+
+	queries["r_vulnerability_affects_featureversion"] = `
+    DELETE FROM Vulnerability_Affects_FeatureVersion
+    WHERE fixedin_id = $1`
+
+	queries["f_featureversion_by_feature"] = `
+    SELECT id, version FROM FeatureVersion WHERE feature_id = $1`
 }
 
 func getQuery(name string) string {
diff --git a/database/pgsql/testdata/data.sql b/database/pgsql/testdata/data.sql
index a555ecf2bc..3033533c2e 100644
--- a/database/pgsql/testdata/data.sql
+++ b/database/pgsql/testdata/data.sql
@@ -3,6 +3,7 @@ INSERT INTO namespace (id, name) VALUES (2, 'debian:8');
 
 INSERT INTO feature (id, namespace_id, name) VALUES (1, 1, 'wechat');
 INSERT INTO feature (id, namespace_id, name) VALUES (2, 1, 'openssl');
+INSERT INTO feature (id, namespace_id, name) VALUES (4, 1, 'libssl');
 INSERT INTO feature (id, namespace_id, name) VALUES (3, 2, 'openssl');
 INSERT INTO featureversion (id, feature_id, version) VALUES (1, 1, '0.5');
 INSERT INTO featureversion (id, feature_id, version) VALUES (2, 2, '1.0');
@@ -23,8 +24,9 @@ INSERT INTO layer_diff_featureversion (id, layer_id, featureversion_id, modifica
 
 INSERT INTO vulnerability (id, namespace_id, name, description, link, severity) VALUES (1, 1, 'CVE-OPENSSL-1-DEB7', 'A vulnerability affecting OpenSSL < 2.0 on Debian 7.0', 'http://google.com/#q=CVE-OPENSSL-1-DEB7', 'High');
 INSERT INTO vulnerability_fixedin_feature (id, vulnerability_id, feature_id, version) VALUES (1, 1, 2, '2.0');
+INSERT INTO vulnerability_fixedin_feature (id, vulnerability_id, feature_id, version) VALUES (2, 1, 4, '1.9-abc');
 INSERT INTO vulnerability_affects_featureversion (id, vulnerability_id, featureversion_id, fixedin_id) VALUES (1, 1, 2, 1); -- CVE-OPENSSL-1-DEB7 affects Debian:7 OpenSSL 1.0
-INSERT INTO vulnerability (id, namespace_id, name, description, link, severity) VALUES (2, 1, 'CVE-NOPE', 'A vulnerability affecting nothing', 'http://google.com/#q=NOPE', 'Negligible');
+INSERT INTO vulnerability (id, namespace_id, name, description, link, severity) VALUES (2, 1, 'CVE-NOPE', 'A vulnerability affecting nothing', '', 'Unknown');
 
 SELECT pg_catalog.setval(pg_get_serial_sequence('namespace', 'id'), (SELECT MAX(id) FROM namespace)+1);
 SELECT pg_catalog.setval(pg_get_serial_sequence('feature', 'id'), (SELECT MAX(id) FROM feature)+1);
diff --git a/database/pgsql/vulnerability.go b/database/pgsql/vulnerability.go
new file mode 100644
index 0000000000..cc7d4f8585
--- /dev/null
+++ b/database/pgsql/vulnerability.go
@@ -0,0 +1,306 @@
+package pgsql
+
+import (
+	"database/sql"
+
+	"github.com/coreos/clair/database"
+	"github.com/coreos/clair/utils"
+	cerrors "github.com/coreos/clair/utils/errors"
+	"github.com/coreos/clair/utils/types"
+	"github.com/guregu/null/zero"
+)
+
+func (pgSQL *pgSQL) FindVulnerability(namespaceName, name string) (database.Vulnerability, error) {
+	vulnerability := database.Vulnerability{
+		Name: name,
+		Namespace: database.Namespace{
+			Name: namespaceName,
+		},
+	}
+
+	// Find Vulnerability.
+	rows, err := pgSQL.Query(getQuery("f_vulnerability"), namespaceName, name)
+	if err != nil {
+		return vulnerability, handleError("f_vulnerability", err)
+	}
+	defer rows.Close()
+
+	// Iterate to scan the Vulnerability and its FixedIn FeatureVersions.
+	for rows.Next() {
+		var featureVersionID zero.Int
+		var featureVersionVersion zero.String
+		var featureVersionFeatureName zero.String
+
+		err := rows.Scan(&vulnerability.ID, &vulnerability.Namespace.ID, &vulnerability.Description,
+			&vulnerability.Link, &vulnerability.Severity, &featureVersionVersion, &featureVersionID,
+			&featureVersionFeatureName)
+		if err != nil {
+			return vulnerability, handleError("f_vulnerability.Scan()", err)
+		}
+
+		if !featureVersionID.IsZero() {
+			// Note that the ID we fill in featureVersion is actually a Feature ID, and not
+			// a FeatureVersion ID.
+			featureVersion := database.FeatureVersion{
+				Model: database.Model{ID: int(featureVersionID.Int64)},
+				Feature: database.Feature{
+					Model:     database.Model{ID: int(featureVersionID.Int64)},
+					Namespace: vulnerability.Namespace,
+					Name:      featureVersionFeatureName.String,
+				},
+				Version: types.NewVersionUnsafe(featureVersionVersion.String),
+			}
+			vulnerability.FixedIn = append(vulnerability.FixedIn, featureVersion)
+		}
+	}
+	if err = rows.Err(); err != nil {
+		return vulnerability, handleError("s_featureversions_vulnerabilities.Rows()", err)
+	}
+	if vulnerability.ID == 0 {
+		return vulnerability, cerrors.ErrNotFound
+	}
+
+	return vulnerability, nil
+}
+
+// FixedIn.Namespace are not necessary, they are overwritten by the vuln.
+func (pgSQL *pgSQL) InsertVulnerabilities(vulnerabilities []database.Vulnerability) error {
+	for _, vulnerability := range vulnerabilities {
+		err := pgSQL.insertVulnerability(vulnerability)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func (pgSQL *pgSQL) insertVulnerability(vulnerability database.Vulnerability) error {
+	// Verify parameters
+	if vulnerability.Name == "" || len(vulnerability.FixedIn) == 0 ||
+		vulnerability.Namespace.Name == "" || !vulnerability.Severity.IsValid() {
+		log.Warning("could not insert an invalid vulnerability")
+		return cerrors.NewBadRequestError("could not insert an invalid vulnerability")
+	}
+
+	for _, fixedInFeatureVersion := range vulnerability.FixedIn {
+		if fixedInFeatureVersion.Feature.Namespace.Name != "" &&
+			fixedInFeatureVersion.Feature.Namespace.Name != vulnerability.Namespace.Name {
+			msg := "could not insert an invalid vulnerability: FixedIn FeatureVersion must be in the " +
+				"same namespace as the Vulnerability"
+			log.Warning(msg)
+			return cerrors.NewBadRequestError(msg)
+		}
+	}
+
+	// Find or insert Vulnerability's Namespace.
+	namespaceID, err := pgSQL.insertNamespace(vulnerability.Namespace)
+	if err != nil {
+		return err
+	}
+
+	// Find vulnerability and its Vulnerability_FixedIn_Features.
+	existingVulnerability, err := pgSQL.FindVulnerability(vulnerability.Namespace.Name,
+		vulnerability.Name)
+	if err != nil && err != cerrors.ErrNotFound {
+		return err
+	}
+
+	// Compute new/updated FixedIn FeatureVersions.
+	var newFixedInFeatureVersions []database.FeatureVersion
+	var updatedFixedInFeatureVersions []database.FeatureVersion
+	if existingVulnerability.ID == 0 {
+		newFixedInFeatureVersions = vulnerability.FixedIn
+	} else {
+		newFixedInFeatureVersions, updatedFixedInFeatureVersions = diffFixedIn(vulnerability,
+			existingVulnerability)
+	}
+
+	if len(newFixedInFeatureVersions) == 0 && len(updatedFixedInFeatureVersions) == 0 {
+		// Nothing to do.
+		return nil
+	}
+
+	// Insert or find the new FeatureVersions.
+	// We already have the Feature IDs in updatedFixedInFeatureVersions because diffFixedIn fills them
+	// in using the existing vulnerability's FixedIn FeatureVersions. Note that even if FixedIn
+	// is type FeatureVersion, the actual stored ID in these structs are the Feature IDs.
+	//
+	// Also, we enforce the namespace of the FeatureVersion in case it was empty. There is a test
+	// above to ensure that the passed Namespace is either the same as the vulnerability or empty.
+	for i := 0; i < len(newFixedInFeatureVersions); i++ {
+		newFixedInFeatureVersions[i].Feature.Namespace.Name = vulnerability.Namespace.Name
+		newFixedInFeatureVersions[i].ID, err = pgSQL.insertFeatureVersion(newFixedInFeatureVersions[i])
+		if err != nil {
+			return err
+		}
+	}
+
+	// Begin transaction.
+	tx, err := pgSQL.Begin()
+	if err != nil {
+		tx.Rollback()
+		return handleError("insertVulnerability.Begin()", err)
+	}
+
+	// Set transaction as SERIALIZABLE.
+	// This is how we ensure that the data in Vulnerability_Affects_FeatureVersion is always
+	// consistent.
+	_, err = tx.Exec(getQuery("set_tx_serializable"))
+	if err != nil {
+		tx.Rollback()
+		return handleError("insertFeatureVersion.set_tx_serializable", err)
+	}
+
+	if existingVulnerability.ID == 0 {
+		// Insert new vulnerability.
+		err = tx.QueryRow(getQuery("i_vulnerability"), namespaceID, vulnerability.Name,
+			vulnerability.Description, vulnerability.Link, &vulnerability.Severity).Scan(&vulnerability.ID)
+		if err != nil {
+			tx.Rollback()
+			return handleError("i_vulnerability", err)
+		}
+	} else {
+		// Update vulnerability
+		_, err = tx.Exec(getQuery("u_vulnerability"), existingVulnerability.ID,
+			vulnerability.Description, vulnerability.Link, &vulnerability.Severity)
+		if err != nil {
+			tx.Rollback()
+			return handleError("u_vulnerability", err)
+		}
+
+		vulnerability.ID = existingVulnerability.ID
+	}
+
+	// Update Vulnerability_FixedIn_Feature and Vulnerability_Affects_FeatureVersion now.
+	err = pgSQL.updateVulnerabilityFeatureVersions(tx, &vulnerability, &existingVulnerability, newFixedInFeatureVersions, updatedFixedInFeatureVersions)
+	if err != nil {
+		tx.Rollback()
+		return err
+	}
+
+	// Commit transaction.
+	err = tx.Commit()
+	if err != nil {
+		tx.Rollback()
+		return handleError("insertVulnerability.Commit()", err)
+	}
+
+	return nil
+}
+
+func diffFixedIn(vulnerability, existingVulnerability database.Vulnerability) (newFixedIn, updatedFixedIn []database.FeatureVersion) {
+	// Build FeatureVersion.Feature.Namespace.Name:FeatureVersion.Feature.Name (NaN) structures.
+	vulnerabilityFixedInNameMap, vulnerabilityFixedInNameSlice := createFeatureVersionNameMap(vulnerability.FixedIn)
+	existingFixedInMapNameMap, existingFixedInNameSlice := createFeatureVersionNameMap(existingVulnerability.FixedIn)
+
+	// Calculate the new FixedIn FeatureVersion NaN and updated ones.
+	newFixedInName := utils.CompareStringLists(vulnerabilityFixedInNameSlice,
+		existingFixedInNameSlice)
+	updatedFixedInName := utils.CompareStringListsInBoth(vulnerabilityFixedInNameSlice,
+		existingFixedInNameSlice)
+
+	for _, nan := range newFixedInName {
+		newFixedIn = append(newFixedIn, vulnerabilityFixedInNameMap[nan])
+	}
+	for _, nan := range updatedFixedInName {
+		fv := existingFixedInMapNameMap[nan]
+		fv.Version = vulnerabilityFixedInNameMap[nan].Version
+		updatedFixedIn = append(updatedFixedIn, fv)
+	}
+
+	return
+}
+
+func createFeatureVersionNameMap(features []database.FeatureVersion) (map[string]database.FeatureVersion, []string) {
+	m := make(map[string]database.FeatureVersion, 0)
+	s := make([]string, 0, len(features))
+
+	for i := 0; i < len(features); i++ {
+		featureVersion := features[i]
+		m[featureVersion.Feature.Name] = featureVersion
+		s = append(s, featureVersion.Feature.Name)
+	}
+
+	return m, s
+}
+
+// TODO(Quentin-M): Add support for removing Vulnerability_FixedIn_Feature when Version = MinVersion.
+//                  We should then update the vulnerability fetcher to do it.
+//                  Also maybe we would delete a Vulnerability if it hasn't any FixedIn.
+// --> And affects
+func (pgSQL *pgSQL) updateVulnerabilityFeatureVersions(tx *sql.Tx, vulnerability, existingVulnerability *database.Vulnerability, newFixedInFeatureVersions, updatedFixedInFeatureVersions []database.FeatureVersion) error {
+	var fixedInID int
+
+	for _, fv := range newFixedInFeatureVersions {
+		// Insert Vulnerability_FixedIn_Feature.
+		err := tx.QueryRow(getQuery("i_vulnerability_fixedin_feature"), vulnerability.ID, fv.ID,
+			&fv.Version).Scan(&fixedInID)
+		if err != nil {
+			return handleError("i_vulnerability_fixedin_feature", err)
+		}
+
+		// Insert Vulnerability_Affects_FeatureVersion.
+		err = linkVulnerabilityToFeatureVersions(tx, fixedInID, vulnerability.ID, fv.ID, fv.Version)
+		if err != nil {
+			return err
+		}
+	}
+
+	for _, fv := range updatedFixedInFeatureVersions {
+		// Update Vulnerability_FixedIn_Feature.
+		err := tx.QueryRow(getQuery("u_vulnerability_fixedin_feature"), vulnerability.ID, fv.ID,
+			&fv.Version).Scan(&fixedInID)
+		if err != nil {
+			return handleError("u_vulnerability_fixedin_feature", err)
+		}
+
+		// Drop all old Vulnerability_Affects_FeatureVersion.
+		_, err = tx.Exec(getQuery("r_vulnerability_affects_featureversion"), fixedInID)
+		if err != nil {
+			return handleError("r_vulnerability_affects_featureversion", err)
+		}
+
+		// Insert Vulnerability_Affects_FeatureVersion.
+		err = linkVulnerabilityToFeatureVersions(tx, fixedInID, vulnerability.ID, fv.ID, fv.Version)
+		if err != nil {
+			return err
+		}
+	}
+
+	return nil
+}
+
+func linkVulnerabilityToFeatureVersions(tx *sql.Tx, fixedInID, vulnerabilityID, featureID int, fixedInVersion types.Version) error {
+	// Find every FeatureVersions of the Feature we want to affect.
+	// TODO(Quentin-M): LIMIT
+	rows, err := tx.Query(getQuery("f_featureversion_by_feature"), featureID)
+	if err == sql.ErrNoRows {
+		return nil
+	}
+	if err != nil {
+		return handleError("f_featureversion_by_feature", err)
+	}
+	defer rows.Close()
+
+	var featureVersionID int
+	var featureVersionVersion types.Version
+	for rows.Next() {
+		err := rows.Scan(&featureVersionID, &featureVersionVersion)
+		if err != nil {
+			return handleError("f_featureversion_by_feature.Scan()", err)
+		}
+
+		if featureVersionVersion.Compare(fixedInVersion) < 0 {
+			_, err := tx.Exec("i_vulnerability_affects_featureversion", vulnerabilityID, featureVersionID,
+				fixedInID)
+			if err != nil {
+				return handleError("i_vulnerability_affects_featureversion", err)
+			}
+		}
+	}
+	if err = rows.Err(); err != nil {
+		return handleError("f_featureversion_by_feature.Rows()", err)
+	}
+
+	return nil
+}
diff --git a/database/pgsql/vulnerability_test.go b/database/pgsql/vulnerability_test.go
new file mode 100644
index 0000000000..690a967013
--- /dev/null
+++ b/database/pgsql/vulnerability_test.go
@@ -0,0 +1,387 @@
+package pgsql
+
+import (
+	"testing"
+
+	"github.com/coreos/clair/database"
+	cerrors "github.com/coreos/clair/utils/errors"
+	"github.com/coreos/clair/utils/types"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestFindVulnerability(t *testing.T) {
+	datastore, err := OpenForTest("FindVulnerability", true)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	defer datastore.Close()
+
+	// Find a vulnerability that does not exist.
+	_, err = datastore.FindVulnerability("", "")
+	assert.Equal(t, cerrors.ErrNotFound, err)
+
+	// Find a normal vulnerability.
+	v1 := database.Vulnerability{
+		Name:        "CVE-OPENSSL-1-DEB7",
+		Description: "A vulnerability affecting OpenSSL < 2.0 on Debian 7.0",
+		Link:        "http://google.com/#q=CVE-OPENSSL-1-DEB7",
+		Severity:    types.High,
+		FixedIn: []database.FeatureVersion{
+			database.FeatureVersion{
+				Feature: database.Feature{Name: "openssl"},
+				Version: types.NewVersionUnsafe("2.0"),
+			},
+			database.FeatureVersion{
+				Feature: database.Feature{Name: "libssl"},
+				Version: types.NewVersionUnsafe("1.9-abc"),
+			},
+		},
+	}
+
+	v1f, err := datastore.FindVulnerability("debian:7", "CVE-OPENSSL-1-DEB7")
+	if assert.Nil(t, err) {
+		equalsVuln(t, &v1, &v1f)
+	}
+
+	// Find a vulnerability that has no link, no severity and no FixedIn.
+	v2 := database.Vulnerability{
+		Name:        "CVE-OPENSSL-1-DEB7",
+		Description: "A vulnerability affecting OpenSSL < 2.0 on Debian 7.0",
+	}
+
+	v2f, err := datastore.FindVulnerability("debian:7", "CVE-NOPE")
+	if assert.Nil(t, err) {
+		equalsVuln(t, &v2, &v2f)
+	}
+}
+
+func TestInsertVulnerability(t *testing.T) {
+	datastore, err := OpenForTest("InsertVulnerability", false)
+	if err != nil {
+		t.Error(err)
+		return
+	}
+	defer datastore.Close()
+
+	// Create some data.
+	n1 := database.Namespace{Name: "TestInsertVulnerabilityNamespace1"}
+	n2 := database.Namespace{Name: "TestInsertVulnerabilityNamespace2"}
+
+	f1 := database.FeatureVersion{
+		Feature: database.Feature{
+			Name:      "TestInsertVulnerabilityFeatureVersion1",
+			Namespace: n1,
+		},
+		Version: types.NewVersionUnsafe("1.0"),
+	}
+	f2 := database.FeatureVersion{
+		Feature: database.Feature{
+			Name:      "TestInsertVulnerabilityFeatureVersion1",
+			Namespace: n2,
+		},
+		Version: types.NewVersionUnsafe("1.0"),
+	}
+	f3 := database.FeatureVersion{
+		Feature: database.Feature{
+			Name: "TestInsertVulnerabilityFeatureVersion2",
+		},
+		Version: types.MaxVersion,
+	}
+	f4 := database.FeatureVersion{
+		Feature: database.Feature{
+			Name: "TestInsertVulnerabilityFeatureVersion2",
+		},
+		Version: types.NewVersionUnsafe("1.4"),
+	}
+	f5 := database.FeatureVersion{
+		Feature: database.Feature{
+			Name: "TestInsertVulnerabilityFeatureVersion3",
+		},
+		Version: types.NewVersionUnsafe("1.5"),
+	}
+	f6 := database.FeatureVersion{
+		Feature: database.Feature{
+			Name: "TestInsertVulnerabilityFeatureVersion4",
+		},
+		Version: types.NewVersionUnsafe("0.1"),
+	}
+
+	// Insert invalid vulnerabilities.
+	for _, vulnerability := range []database.Vulnerability{
+		database.Vulnerability{
+			Name:      "",
+			Namespace: n1,
+			FixedIn:   []database.FeatureVersion{f1},
+			Severity:  types.Unknown,
+		},
+		database.Vulnerability{
+			Name:      "TestInsertVulnerability0",
+			Namespace: database.Namespace{},
+			FixedIn:   []database.FeatureVersion{f1},
+			Severity:  types.Unknown,
+		},
+		database.Vulnerability{
+			Name:      "TestInsertVulnerability0-",
+			Namespace: database.Namespace{},
+			FixedIn:   []database.FeatureVersion{f1},
+		},
+		database.Vulnerability{
+			Name:      "TestInsertVulnerability0",
+			Namespace: n1,
+			FixedIn:   []database.FeatureVersion{f1},
+			Severity:  types.Priority(""),
+		},
+		database.Vulnerability{
+			Name:      "TestInsertVulnerability0",
+			Namespace: n1,
+			FixedIn:   []database.FeatureVersion{f2},
+			Severity:  types.Unknown,
+		},
+	} {
+		err := datastore.InsertVulnerabilities([]database.Vulnerability{vulnerability})
+		assert.Error(t, err)
+	}
+
+	// Insert a simple vulnerability and find it.
+	v1 := database.Vulnerability{
+		Name:        "TestInsertVulnerability1",
+		Namespace:   n1,
+		FixedIn:     []database.FeatureVersion{f1, f3, f6},
+		Severity:    types.Low,
+		Description: "TestInsertVulnerabilityDescription1",
+		Link:        "TestInsertVulnerabilityLink1",
+	}
+	err = datastore.InsertVulnerabilities([]database.Vulnerability{v1})
+	if assert.Nil(t, err) {
+		v1f, err := datastore.FindVulnerability(n1.Name, v1.Name)
+		if assert.Nil(t, err) {
+			equalsVuln(t, &v1, &v1f)
+		}
+	}
+
+	// Update vulnerability.
+	v1.Description = "TestInsertVulnerabilityLink2"
+	v1.Link = "TestInsertVulnerabilityLink2"
+	v1.Severity = types.High
+	// Update f3 by f4, add fixed by f5, add fixed by f6 which already exists.
+	// TODO(Quentin-M): Remove FixedIn.
+	v1.FixedIn = []database.FeatureVersion{f4, f5, f6}
+
+	err = datastore.InsertVulnerabilities([]database.Vulnerability{v1})
+	if assert.Nil(t, err) {
+		v1f, err := datastore.FindVulnerability(n1.Name, v1.Name)
+		if assert.Nil(t, err) {
+			// We already had f1 before the update.
+			// Add it to the struct for comparison.
+			v1.FixedIn = append(v1.FixedIn, f1)
+			equalsVuln(t, &v1, &v1f)
+		}
+	}
+}
+
+func equalsVuln(t *testing.T, expected, actual *database.Vulnerability) {
+	assert.Equal(t, expected.Name, actual.Name)
+	assert.Equal(t, expected.Namespace.Name, actual.Namespace.Name)
+	assert.Equal(t, expected.Description, actual.Description)
+	assert.Equal(t, expected.Link, actual.Link)
+	assert.Equal(t, expected.Severity, actual.Severity)
+	if assert.Len(t, actual.FixedIn, len(expected.FixedIn)) {
+		for _, actualFeatureVersion := range actual.FixedIn {
+			found := false
+			for _, expectedFeatureVersion := range expected.FixedIn {
+				if expectedFeatureVersion.Feature.Name == actualFeatureVersion.Feature.Name {
+					found = true
+
+					assert.Equal(t, expected.Namespace.Name, actualFeatureVersion.Feature.Namespace.Name)
+					assert.Equal(t, expectedFeatureVersion.Version, actualFeatureVersion.Version)
+				}
+			}
+			if !found {
+				t.Errorf("unexpected package %s in %s", actualFeatureVersion.Feature.Name, expected.Name)
+			}
+		}
+	}
+}
+
+// TODO Test Affects in Feature_Version and here.
+
+//
+// // Some data
+// vuln1 := &database.Vulnerability{ID: "test1", Link: "link1", Priority: types.Medium, Description: "testDescription1", FixedInNodes: []string{"pkg1"}}
+// vuln2 := &database.Vulnerability{ID: "test2", Link: "link2", Priority: types.High, Description: "testDescription2", FixedInNodes: []string{"pkg1", "pkg2"}}
+// vuln3 := &database.Vulnerability{ID: "test3", Link: "link3", Priority: types.High, FixedInNodes: []string{"pkg3"}} // Empty description
+//
+// // Insert some vulnerabilities
+// _, err := InsertVulnerabilities([]*database.Vulnerability{vuln1, vuln2, vuln3})
+// if assert.Nil(t, err) {
+// 	// Find one of the vulnerabilities we just inserted and verify its content
+// 	v1, err := FindOnedatabase.Vulnerability(vuln1.ID, Fielddatabase.VulnerabilityAll)
+// 	if assert.Nil(t, err) && assert.NotNil(t, v1) {
+// 		assert.Equal(t, vuln1.ID, v1.ID)
+// 		assert.Equal(t, vuln1.Link, v1.Link)
+// 		assert.Equal(t, vuln1.Priority, v1.Priority)
+// 		assert.Equal(t, vuln1.Description, v1.Description)
+// 		if assert.Len(t, v1.FixedInNodes, 1) {
+// 			assert.Equal(t, vuln1.FixedInNodes[0], v1.FixedInNodes[0])
+// 		}
+// 	}
+// }
+//
+// // Update a database.Vulnerability and verify its new content
+// pkg1 := &Package{OS: "testOS", Name: "testpkg1", Version: types.NewVersionUnsafe("1.0")}
+// InsertPackages([]*Package{pkg1})
+// vuln5 := &database.Vulnerability{ID: "test5", Link: "link5", Priority: types.Medium, Description: "testDescription5", FixedInNodes: []string{pkg1.Node}}
+//
+// _, err = InsertVulnerabilities([]*database.Vulnerability{vuln5})
+// if assert.Nil(t, err) {
+// 	// Partial updates
+// 	// # Just a field update
+// 	vuln5b := &database.Vulnerability{ID: "test5", Priority: types.High}
+// 	_, err := InsertVulnerabilities([]*database.Vulnerability{vuln5b})
+// 	if assert.Nil(t, err) {
+// 		v5b, err := FindOnedatabase.Vulnerability(vuln5b.ID, Fielddatabase.VulnerabilityAll)
+// 		if assert.Nil(t, err) && assert.NotNil(t, v5b) {
+// 			assert.Equal(t, vuln5b.ID, v5b.ID)
+// 			assert.Equal(t, vuln5b.Priority, v5b.Priority)
+//
+// 			if assert.Len(t, v5b.FixedInNodes, 1) {
+// 				assert.Contains(t, v5b.FixedInNodes, pkg1.Node)
+// 			}
+// 		}
+// 	}
+//
+// 	// # Just a field update, twice in the same transaction
+// 	vuln5b1 := &database.Vulnerability{ID: "test5", Link: "http://foo.bar"}
+// 	vuln5b2 := &database.Vulnerability{ID: "test5", Link: "http://bar.foo"}
+// 	_, err = InsertVulnerabilities([]*database.Vulnerability{vuln5b1, vuln5b2})
+// 	if assert.Nil(t, err) {
+// 		v5b2, err := FindOnedatabase.Vulnerability(vuln5b2.ID, Fielddatabase.VulnerabilityAll)
+// 		if assert.Nil(t, err) && assert.NotNil(t, v5b2) {
+// 			assert.Equal(t, vuln5b2.Link, v5b2.Link)
+// 		}
+// 	}
+//
+// 	// # All fields except fixedIn update
+// 	vuln5c := &database.Vulnerability{ID: "test5", Link: "link5c", Priority: types.Critical, Description: "testDescription5c"}
+// 	_, err = InsertVulnerabilities([]*database.Vulnerability{vuln5c})
+// 	if assert.Nil(t, err) {
+// 		v5c, err := FindOnedatabase.Vulnerability(vuln5c.ID, Fielddatabase.VulnerabilityAll)
+// 		if assert.Nil(t, err) && assert.NotNil(t, v5c) {
+// 			assert.Equal(t, vuln5c.ID, v5c.ID)
+// 			assert.Equal(t, vuln5c.Link, v5c.Link)
+// 			assert.Equal(t, vuln5c.Priority, v5c.Priority)
+// 			assert.Equal(t, vuln5c.Description, v5c.Description)
+//
+// 			if assert.Len(t, v5c.FixedInNodes, 1) {
+// 				assert.Contains(t, v5c.FixedInNodes, pkg1.Node)
+// 			}
+// 		}
+// 	}
+//
+// 	// Complete update
+// 	pkg2 := &Package{OS: "testOS", Name: "testpkg1", Version: types.NewVersionUnsafe("1.1")}
+// 	pkg3 := &Package{OS: "testOS", Name: "testpkg2", Version: types.NewVersionUnsafe("1.0")}
+// 	InsertPackages([]*Package{pkg2, pkg3})
+// 	vuln5d := &database.Vulnerability{ID: "test5", Link: "link5d", Priority: types.Low, Description: "testDescription5d", FixedInNodes: []string{pkg2.Node, pkg3.Node}}
+//
+// 	_, err = InsertVulnerabilities([]*database.Vulnerability{vuln5d})
+// 	if assert.Nil(t, err) {
+// 		v5d, err := FindOnedatabase.Vulnerability(vuln5d.ID, Fielddatabase.VulnerabilityAll)
+// 		if assert.Nil(t, err) && assert.NotNil(t, v5d) {
+// 			assert.Equal(t, vuln5d.ID, v5d.ID)
+// 			assert.Equal(t, vuln5d.Link, v5d.Link)
+// 			assert.Equal(t, vuln5d.Priority, v5d.Priority)
+// 			assert.Equal(t, vuln5d.Description, v5d.Description)
+//
+// 			// Here, we ensure that a database.Vulnerability can only be fixed by one package of a given branch at a given time
+// 			// And that we can add new fixed packages as well
+// 			if assert.Len(t, v5d.FixedInNodes, 2) {
+// 				assert.NotContains(t, v5d.FixedInNodes, pkg1.Node)
+// 			}
+// 		}
+// 	}
+// }
+//
+// // Create and update a database.Vulnerability's packages (and from the same branch) in the same batch
+// pkg1 = &Package{OS: "testOS", Name: "testpkg1", Version: types.NewVersionUnsafe("1.0")}
+// pkg1b := &Package{OS: "testOS", Name: "testpkg1", Version: types.NewVersionUnsafe("1.1")}
+// InsertPackages([]*Package{pkg1, pkg1b})
+//
+// // # Two updates of the same database.Vulnerability in the same batch with packages of the same branch
+// pkg0 := &Package{OS: "testOS", Name: "testpkg0", Version: types.NewVersionUnsafe("1.0")}
+// InsertPackages([]*Package{pkg0})
+// _, err = InsertVulnerabilities([]*database.Vulnerability{&database.Vulnerability{ID: "test7", Link: "link7", Priority: types.Medium, Description: "testDescription7", FixedInNodes: []string{pkg0.Node}}})
+// if assert.Nil(t, err) {
+// 	vuln7b := &database.Vulnerability{ID: "test7", FixedInNodes: []string{pkg1.Node}}
+// 	vuln7c := &database.Vulnerability{ID: "test7", FixedInNodes: []string{pkg1b.Node}}
+// 	_, err = InsertVulnerabilities([]*database.Vulnerability{vuln7b, vuln7c})
+// 	if assert.Nil(t, err) {
+// 		v7, err := FindOnedatabase.Vulnerability("test7", Fielddatabase.VulnerabilityAll)
+// 		if assert.Nil(t, err) && assert.Len(t, v7.FixedInNodes, 2) {
+// 			assert.Contains(t, v7.FixedInNodes, pkg0.Node)
+// 			assert.NotContains(t, v7.FixedInNodes, pkg1.Node)
+// 			assert.Contains(t, v7.FixedInNodes, pkg1b.Node)
+// 		}
+// 	}
+// }
+
+// func TestInsertVulnerabilityNotifications(t *testing.T) {
+// 	Open(&config.DatabaseConfig{Type: "memstore"})
+// 	defer Close()
+//
+// 	pkg1 := &Package{OS: "testOS", Name: "testpkg1", Version: types.NewVersionUnsafe("1.0")}
+// 	pkg1b := &Package{OS: "testOS", Name: "testpkg1", Version: types.NewVersionUnsafe("1.2")}
+// 	pkg2 := &Package{OS: "testOS", Name: "testpkg2", Version: types.NewVersionUnsafe("1.0")}
+// 	InsertPackages([]*Package{pkg1, pkg1b, pkg2})
+//
+// 	// Newdatabase.VulnerabilityNotification
+// 	vuln1 := &database.Vulnerability{ID: "test1", Link: "link1", Priority: types.Medium, Description: "testDescription1", FixedInNodes: []string{pkg1.Node}}
+// 	vuln2 := &database.Vulnerability{ID: "test2", Link: "link2", Priority: types.High, Description: "testDescription2", FixedInNodes: []string{pkg1.Node, pkg2.Node}}
+// 	vuln1b := &database.Vulnerability{ID: "test1", Priority: types.High, FixedInNodes: []string{"pkg3"}}
+// 	notifications, err := InsertVulnerabilities([]*database.Vulnerability{vuln1, vuln2, vuln1b})
+// 	if assert.Nil(t, err) {
+// 		// We should only have two Newdatabase.VulnerabilityNotification notifications: one for test1 and one for test2
+// 		// We should not have a database.VulnerabilityPriorityIncreasedNotification or a database.VulnerabilityPackageChangedNotification
+// 		// for test1 because it is in the same batch
+// 		if assert.Len(t, notifications, 2) {
+// 			for _, n := range notifications {
+// 				_, ok := n.(*Newdatabase.VulnerabilityNotification)
+// 				assert.True(t, ok)
+// 			}
+// 		}
+// 	}
+//
+// 	// database.VulnerabilityPriorityIncreasedNotification
+// 	vuln1c := &database.Vulnerability{ID: "test1", Priority: types.Critical}
+// 	notifications, err = InsertVulnerabilities([]*database.Vulnerability{vuln1c})
+// 	if assert.Nil(t, err) {
+// 		if assert.Len(t, notifications, 1) {
+// 			if nn, ok := notifications[0].(*database.VulnerabilityPriorityIncreasedNotification); assert.True(t, ok) {
+// 				assert.Equal(t, vuln1b.Priority, nn.OldPriority)
+// 				assert.Equal(t, vuln1c.Priority, nn.NewPriority)
+// 			}
+// 		}
+// 	}
+//
+// 	notifications, err = InsertVulnerabilities([]*database.Vulnerability{&database.Vulnerability{ID: "test1", Priority: types.Low}})
+// 	assert.Nil(t, err)
+// 	assert.Len(t, notifications, 0)
+//
+// 	// database.VulnerabilityPackageChangedNotification
+// 	vuln1e := &database.Vulnerability{ID: "test1", FixedInNodes: []string{pkg1b.Node}}
+// 	vuln1f := &database.Vulnerability{ID: "test1", FixedInNodes: []string{pkg2.Node}}
+// 	notifications, err = InsertVulnerabilities([]*database.Vulnerability{vuln1e, vuln1f})
+// 	if assert.Nil(t, err) {
+// 		if assert.Len(t, notifications, 1) {
+// 			if nn, ok := notifications[0].(*database.VulnerabilityPackageChangedNotification); assert.True(t, ok) {
+// 				// Here, we say that pkg1b fixes the database.Vulnerability, but as pkg1b is in
+// 				// the same branch as pkg1, pkg1 should be removed and pkg1b added
+// 				// We also add pkg2 as fixed
+// 				assert.Contains(t, nn.AddedFixedInNodes, pkg1b.Node)
+// 				assert.Contains(t, nn.RemovedFixedInNodes, pkg1.Node)
+//
+// 				assert.Contains(t, nn.AddedFixedInNodes, pkg2.Node)
+// 			}
+// 		}
+// 	}
diff --git a/utils/http/http.go b/utils/http/http.go
index 81dfdc19ae..1aac81f3fd 100644
--- a/utils/http/http.go
+++ b/utils/http/http.go
@@ -26,7 +26,7 @@ import (
 	"github.com/coreos/clair/worker"
 )
 
-// MaxPostSize is the maximum number of bytes that ParseHTTPBody reads from an http.Request.Body.
+// MaxBodySize is the maximum number of bytes that ParseHTTPBody reads from an http.Request.Body.
 const MaxBodySize int64 = 1048576
 
 // WriteHTTP writes a JSON-encoded object to a http.ResponseWriter, as well as
@@ -54,7 +54,7 @@ func WriteHTTPError(w http.ResponseWriter, httpStatus int, err error) {
 			switch err {
 			case cerrors.ErrNotFound:
 				httpStatus = http.StatusNotFound
-			case database.ErrTransaction, database.ErrBackendException:
+			case database.ErrBackendException:
 				httpStatus = http.StatusServiceUnavailable
 			case worker.ErrParentUnknown, worker.ErrUnsupported, utils.ErrCouldNotExtract, utils.ErrExtractedFileTooBig:
 				httpStatus = http.StatusBadRequest
diff --git a/utils/string.go b/utils/string.go
index 6e95887472..a366c2f549 100644
--- a/utils/string.go
+++ b/utils/string.go
@@ -22,7 +22,7 @@ import (
 
 var urlParametersRegexp = regexp.MustCompile(`(\?|\&)([^=]+)\=([^ &]+)`)
 
-// Hash returns an unique hash of the given string
+// Hash returns an unique hash of the given string.
 func Hash(str string) string {
 	h := sha1.New()
 	h.Write([]byte(str))
@@ -30,13 +30,13 @@ func Hash(str string) string {
 	return hex.EncodeToString(bs)
 }
 
-// CleanURL removes all parameters from an URL
+// CleanURL removes all parameters from an URL.
 func CleanURL(str string) string {
 	return urlParametersRegexp.ReplaceAllString(str, "")
 }
 
 // Contains looks for a string into an array of strings and returns whether
-// the string exists
+// the string exists.
 func Contains(needle string, haystack []string) bool {
 	for _, h := range haystack {
 		if h == needle {
@@ -46,22 +46,41 @@ func Contains(needle string, haystack []string) bool {
 	return false
 }
 
-// CompareStringLists returns the strings which are present in X but not in Y
+// CompareStringLists returns the strings that are present in X but not in Y.
 func CompareStringLists(X, Y []string) []string {
-	m := make(map[string]int)
+	m := make(map[string]bool)
 
 	for _, y := range Y {
-		m[y] = 1
+		m[y] = true
 	}
 
 	diff := []string{}
 	for _, x := range X {
-		if m[x] > 0 {
+		if m[x] {
 			continue
 		}
 
 		diff = append(diff, x)
-		m[x] = 1
+		m[x] = true
+	}
+
+	return diff
+}
+
+// CompareStringListsInBoth returns the strings that are present in both X and Y.
+func CompareStringListsInBoth(X, Y []string) []string {
+	m := make(map[string]struct{})
+
+	for _, y := range Y {
+		m[y] = struct{}{}
+	}
+
+	diff := []string{}
+	for _, x := range X {
+		if _, e := m[x]; e {
+			diff = append(diff, x)
+			delete(m, x)
+		}
 	}
 
 	return diff
diff --git a/utils/types/priority.go b/utils/types/priority.go
index f8f1094296..aac56d40f4 100644
--- a/utils/types/priority.go
+++ b/utils/types/priority.go
@@ -106,5 +106,5 @@ func (p *Priority) Scan(value interface{}) error {
 }
 
 func (p *Priority) Value() (driver.Value, error) {
-	return p, nil
+	return string(*p), nil
 }
diff --git a/utils/utils_test.go b/utils/utils_test.go
index aafcc2dc4b..8962c84f24 100644
--- a/utils/utils_test.go
+++ b/utils/utils_test.go
@@ -29,7 +29,16 @@ const fileToDownload = "http://www.google.com/robots.txt"
 
 // TestDiff tests the diff.go source file
 func TestDiff(t *testing.T) {
-	assert.NotContains(t, CompareStringLists([]string{"a", "b", "a"}, []string{"a", "c"}), "a")
+	cmp := CompareStringLists([]string{"a", "b", "b", "a"}, []string{"a", "c"})
+	assert.Len(t, cmp, 1)
+	assert.NotContains(t, cmp, "a")
+	assert.Contains(t, cmp, "b")
+
+	cmp = CompareStringListsInBoth([]string{"a", "a", "b", "c"}, []string{"a", "c", "c"})
+	assert.Len(t, cmp, 2)
+	assert.NotContains(t, cmp, "b")
+	assert.Contains(t, cmp, "a")
+	assert.Contains(t, cmp, "c")
 }
 
 // TestExec tests the exec.go source file