Skip NULL values.

lesovsky · May 15, 2021 · 20569d7 · 20569d7
1 parent 580fbb5
commit 20569d7
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Showing 2 changed files with 14 additions and 3 deletions.
diff --git a/internal/collector/collector_common.go b/internal/collector/collector_common.go
@@ -282,6 +282,11 @@ func updateMultipleMetrics(row []sql.NullString, desc typedDesc, colnames []stri
 			}
 
 			for i, resColname := range colnames { // walk through column names from data row
+				// Skip NULL values.
+				if !row[i].Valid {
+					continue
+				}
+
 				// Check for value.
 				if descColname == resColname && !valueOK {
 					var err error
@@ -343,6 +348,11 @@ func updateSingleMetric(row []sql.NullString, desc typedDesc, colnames []string,
 	}
 
 	for i, colname := range colnames {
+		// Skip NULL values.
+		if !row[i].Valid {
+			continue
+		}
+
 		// Check for value.
 		if colname == desc.value {
 			var err error

diff --git a/internal/collector/collector_common_test.go b/internal/collector/collector_common_test.go
@@ -377,10 +377,11 @@ func Test_updateMetrics(t *testing.T) {
 
 func Test_updateMultipleMetrics(t *testing.T) {
 	row := []sql.NullString{
+		{String: "", Valid: false},                                                               // NULL value
 		{String: "852", Valid: true}, {String: "456", Valid: true}, {String: "753", Valid: true}, // ins, upd, del
 		{String: "example", Valid: true}, // relname
 	}
-	colnames := []string{"inserted", "updated", "deleted", "relname"}
+	colnames := []string{"nullable", "inserted", "updated", "deleted", "relname"}
 
 	testcases := []struct {
 		desc         typedDesc
@@ -473,9 +474,9 @@ func Test_updateMultipleMetrics(t *testing.T) {
 
 func Test_updateSingleMetric(t *testing.T) {
 	row := []sql.NullString{
-		{String: "123", Valid: true}, {String: "987654", Valid: true}, {String: "example", Valid: true},
+		{String: "123", Valid: true}, {String: "987654", Valid: true}, {String: "example", Valid: true}, {String: "", Valid: false},
 	}
-	colnames := []string{"seq_scan", "idx_scan", "relname"}
+	colnames := []string{"seq_scan", "idx_scan", "relname", "nullable"}
 
 	testcases := []struct {
 		desc         typedDesc