add ON CONFLICT DO NOTHING for insert

Signed-off-by: jason yang <[email protected]>

pika.go

@@ -130,7 +130,7 @@ type QuerySet[T any] interface {
 	// Query related methods
 
 	// CreateQuery returns the query and args for Create
-	CreateQuery(value *T) (string, []interface{})
+	CreateQuery(value *T, ignoreConflict bool) (string, []interface{})
 
 	// UpdateQuery returns the query and args for Update
 	UpdateQuery(value *T) (string, []interface{})
@@ -165,6 +165,9 @@ type QuerySet[T any] interface {
 	Exclude(excludes ...string) QuerySet[T]
 	// Include fields
 	Include(includes ...string) QuerySet[T]
+
+	// CreateIgnore creates a new value but will not return error if conflict occurs
+	CreateIgnore(value *T) error
 }
 
 func NewArgs() *orderedmap.OrderedMap[string, any] {

pika_psql.go

@@ -255,18 +255,30 @@ func (b *basePsql[T]) ClearAll() QuerySet[T] {
 
 // Create creates a new record in the database.
 func (b *basePsql[T]) Create(x *T) error {
+	return b.create(x, false)
+}
+
+func (b *basePsql[T]) CreateIgnore(x *T) error {
+	return b.create(x, true)
+}
+
+func (b *basePsql[T]) create(x *T, ignoreConflict bool) error {
 	if b.err != nil {
 		return b.err
 	}
 
 	origIgnoreOrderBy := b.ignoreOrderBy
 	b.ignoreOrderBy = true
-	q, args := b.CreateQuery(x)
+	q, args := b.CreateQuery(x, ignoreConflict)
 	b.ignoreOrderBy = origIgnoreOrderBy
 
 	// Execute query
 	err := b.psql.Queryable().Get(x, q, args...)
 	if err != nil {
+		// ignore no rows in resultset error when ignoreConflict is set to true, this is a normal case
+		if errors.Is(err, sql.ErrNoRows) && ignoreConflict {
+			return nil
+		}
 		return err
 	}
 
@@ -468,8 +480,8 @@ func (b *basePsql[T]) ResetOrderBy() QuerySet[T] {
 }
 
 // CreateQuery returns the query and arguments for Create
-func (b *basePsql[T]) CreateQuery(x *T) (string, []interface{}) {
-	q, args := b.psqlCreateQuery(x)
+func (b *basePsql[T]) CreateQuery(x *T, ignoreConflict bool) (string, []interface{}) {
+	q, args := b.psqlCreateQuery(x, ignoreConflict)
 	logger.Debugf("Pika query: %s", q)
 
 	return q, args
@@ -1126,7 +1138,7 @@ func (b *basePsql[T]) psqlCountQuery() string {
 	return q
 }
 
-func (b *basePsql[T]) psqlCreateQuery(value *T) (string, []any) {
+func (b *basePsql[T]) psqlCreateQuery(value *T, ignoreConflict bool) (string, []any) {
 	// Get info from metadata
 	tableName := b.metadata[PikaMetadataTableName]
 	modelName := b.metadata[pikaMetadataModelName]
@@ -1178,7 +1190,11 @@ func (b *basePsql[T]) psqlCreateQuery(value *T) (string, []any) {
 	// Remove the model name prefix from the select list
 	// since we are inserting into the table
 	selectList = strings.Replace(selectList, fmt.Sprintf("\"%s\".", modelName), "", -1)
-	q := fmt.Sprintf("INSERT INTO \"%s\" (%s) VALUES (%s) RETURNING %s", tableName, columnStr, valueStr, selectList)
+	conflict := ""
+	if ignoreConflict {
+		conflict = " ON CONFLICT DO NOTHING"
+	}
+	q := fmt.Sprintf("INSERT INTO \"%s\" (%s) VALUES (%s)%s RETURNING %s", tableName, columnStr, valueStr, conflict, selectList)
 
 	// Convert value to arguments
 	args := make([]interface{}, 0, ref.Elem().NumField())

pika_psql_test.go

@@ -1120,7 +1120,7 @@ func TestCreate(t *testing.T) {
 
 	expectedQuery := `INSERT INTO "simple_model_create" ("title", "description") VALUES ($1, $2) RETURNING "id", "title", "description"`
 	expectedArgs := []interface{}{"test", "test-description"}
-	actualQuery, actualArgs := qs.CreateQuery(&entry)
+	actualQuery, actualArgs := qs.CreateQuery(&entry, false)
 	require.Equal(t, expectedQuery, actualQuery)
 	require.Equal(t, expectedArgs, actualArgs)
 
@@ -1144,6 +1144,53 @@ func TestCreate(t *testing.T) {
 	require.Equal(t, entry.Description, x[0].Description)
 }
 
+func TestCreateIgnore(t *testing.T) {
+	psql := newPsql(t)
+	createTestModelCreate(t, psql)
+	qs := Q[simpleModelCreate](psql)
+
+	// Create a new entry
+	entry := simpleModelCreate{
+		ID:          1,
+		Title:       "test",
+		Description: "test-description",
+	}
+
+	expectedQuery := `INSERT INTO "simple_model_create" ("id", "title", "description") VALUES ($1, $2, $3) ON CONFLICT DO NOTHING RETURNING "id", "title", "description"`
+	expectedArgs := []interface{}{1, "test", "test-description"}
+	actualQuery, actualArgs := qs.CreateQuery(&entry, true)
+	require.Equal(t, expectedQuery, actualQuery)
+	require.Equal(t, expectedArgs, actualArgs)
+
+	err := qs.Create(&entry)
+	require.Nil(t, err)
+	require.Equal(t, 1, entry.ID)
+
+	// create again will cause duplication error
+	err = qs.Create(&entry)
+	require.NotNil(t, err)
+	require.Contains(t, err.Error(), "duplicate key value violates unique constraint")
+
+	// createignore will not throw out the error
+	err = qs.CreateIgnore(&entry)
+	require.Nil(t, err)
+
+	// Select the entry and check if it is the same
+	qs = Q[simpleModelCreate](psql)
+	args := NewArgs()
+	args.Set("id", entry.ID)
+	args.Set("title", entry.Title)
+	args.Set("description", entry.Description)
+	qs = qs.Filter("id=:id", "title=:title", "description=:description").Args(args)
+
+	x, err := qs.All()
+	require.Nil(t, err)
+	require.Equal(t, 1, len(x))
+	require.Equal(t, entry.ID, x[0].ID)
+	require.Equal(t, entry.Title, x[0].Title)
+	require.Equal(t, entry.Description, x[0].Description)
+}
+
 func TestUpdate(t *testing.T) {
 	psql := newPsql(t)
 	createTestModelCreate(t, psql)