convert to microsecond precision timestamps

migrations/20240120195122_init.up.sql

@@ -8,8 +8,8 @@ CREATE TABLE IF NOT EXISTS spans(
     "__duration" INTEGER,
     "name" TEXT,
     "kind" TEXT,
-    "start_time" INTEGER,
-    "end_time" INTEGER,
+    "start_time" INTEGER, -- start_time is a microsecond precision unix timestamp
+    "end_time" INTEGER, -- end_time is a microsecond precision unix timestamp
     "status_code" INTEGER,
     "status_description" TEXT,
     "attributes" TEXT,
@@ -23,7 +23,7 @@ CREATE TABLE IF NOT EXISTS spans(
 
 CREATE TABLE IF NOT EXISTS events(
     "span_id" BLOB,
-    "timestamp" INTEGER,
+    "timestamp" INTEGER, -- timestamp is a microsecond precision unix timestamp
     "name" TEXT,
     "attributes" TEXT,
     "dropped_attributes_count" INTEGER,

migrations/20240209144007_microsecond_timestamps.down.sql

@@ -0,0 +1,4 @@
+ALTER TABLE spans DROP COLUMN start_time;
+ALTER TABLE spans DROP COLUMN end_time;
+ALTER TABLE spans RENAME COLUMN start_time_bak TO start_time;
+ALTER TABLE spans RENAME COLUMN end_time_back TO end_time;

migrations/20240209144007_microsecond_timestamps.up.sql

@@ -0,0 +1,7 @@
+-- Backup the start_time and end_time column values and convert existing
+-- timestamps to microsecond precision
+-- TODO(wperron): remove this before publishing
+ALTER TABLE spans RENAME COLUMN start_time TO start_time_bak;
+ALTER TABLE spans RENAME COLUMN end_time TO end_time;
+ALTER TABLE spans ADD COLUMN (start_time INTEGER ) DEFAULT (start_time_bak * 1000);
+ALTER TABLE spans ADD COLUMN (end_time INTEGER ) DEFAULT (end_time * 1000);

sqlite_exporter.go

@@ -6,6 +6,7 @@ import (
 	"database/sql"
 	"encoding/json"
 	"fmt"
+	"time"
 
 	_ "github.com/mattn/go-sqlite3"
 	"go.opentelemetry.io/collector/component"
@@ -198,8 +199,9 @@ func (e *sqliteExporter) ConsumeTraces(ctx context.Context, traces ptrace.Traces
 					dur.Microseconds(),
 					span.Name(),
 					span.Kind().String(),
-					span.StartTimestamp().AsTime().Unix(),
-					span.EndTimestamp().AsTime().Unix(),
+					// Use microsecond precision for start and timestamps
+					unixMicro(span.StartTimestamp().AsTime()),
+					unixMicro(span.EndTimestamp().AsTime()),
 					span.Status().Code(),
 					span.Status().Message(),
 					attrs,
@@ -228,7 +230,7 @@ func (e *sqliteExporter) ConsumeTraces(ctx context.Context, traces ptrace.Traces
 
 					_, err = stmt.ExecContext(ctx,
 						spanidbs,
-						event.Timestamp().AsTime().Unix(),
+						unixMicro(event.Timestamp().AsTime()),
 						event.Name(),
 						attrs,
 						event.DroppedAttributesCount(),
@@ -278,3 +280,7 @@ func (e *sqliteExporter) ConsumeTraces(ctx context.Context, traces ptrace.Traces
 func pcommonMapAsJSON(m pcommon.Map) ([]byte, error) {
 	return json.Marshal(m.AsRaw())
 }
+
+func unixMicro(t time.Time) int64 {
+	return t.UnixNano() / 1000
+}

sqlite_exporter_test.go

@@ -152,8 +152,8 @@ func Test_ExporterExportSpan(t *testing.T) {
 	assert.Equal(t, 5000, duration)
 	assert.Equal(t, "span1", name)
 	assert.Equal(t, ptrace.SpanKindServer.String(), kind)
-	assert.Equal(t, now.Add(-5*time.Millisecond).Unix(), int64(startTime))
-	assert.Equal(t, now.Unix(), int64(endTime))
+	assert.Equal(t, unixMicro(now.Add(-5*time.Millisecond)), int64(startTime))
+	assert.Equal(t, unixMicro(now), int64(endTime))
 	assert.Equal(t, int(ptrace.StatusCodeOk), statusCode)
 	assert.Equal(t, ptrace.StatusCodeOk.String(), statusDescription)
 	assert.Equal(t, "{\"http.method\":\"GET\",\"http.status_code\":200}", attributes)
@@ -191,8 +191,8 @@ func Test_ExporterExportSpan(t *testing.T) {
 	assert.Equal(t, 3000, duration)
 	assert.Equal(t, "span2", name)
 	assert.Equal(t, ptrace.SpanKindInternal.String(), kind)
-	assert.Equal(t, now.Add(-4*time.Millisecond).Unix(), int64(startTime))
-	assert.Equal(t, now.Add(-1*time.Millisecond).Unix(), int64(endTime))
+	assert.Equal(t, unixMicro(now.Add(-4*time.Millisecond)), int64(startTime))
+	assert.Equal(t, unixMicro(now.Add(-1*time.Millisecond)), int64(endTime))
 	assert.Equal(t, int(ptrace.StatusCodeOk), statusCode)
 	assert.Equal(t, ptrace.StatusCodeOk.String(), statusDescription)
 	assert.Equal(t, "{\"custom.key\":\"custom-value\"}", attributes)