Insert or update: TimescaleDB and DuckDB
Every file of the TimescaleDB and DuckDB versions side by side, with the lines that differ marked. 5 parameter or column types differ in Go.
Configuration
sgl.yamldiffers
TimescaleDB
DuckDB
1
version: 11
version: 12
2
3
databases:3
databases:4
- name: stock4
- name: stock5
dialect: postgres5
dialect: duckdb6
migrations: db/migrations6
migrations: db/migrations7
queries: db/queries7
queries: db/queries8
go:8
go:9
package: store9
package: store10
out: internal/store10
out: internal/store11
driver: database/sql12
migrate:13
dsn: ${env:DATABASE_URL}Migrations
db/migrations/0001_stock.up.sqldiffers
TimescaleDB
DuckDB
1
CREATE TABLE stock (1
CREATE TABLE stock (2
item TEXT PRIMARY KEY,2
item VARCHAR PRIMARY KEY,3
quantity BIGINT NOT NULL,3
quantity INTEGER NOT NULL,4
deliveries BIGINT NOT NULL DEFAULT 04
deliveries INTEGER NOT NULL DEFAULT 05
);5
);db/migrations/0001_stock.down.sqlidentical
TimescaleDB
DuckDB
1
DROP TABLE stock;1
DROP TABLE stock;Queries
ReceiveDeliverydiffers
TimescaleDB · db/queries/stock.sql
DuckDB · db/queries/stock.sql
1
-- sgl.query(ReceiveDelivery, one)1
-- sgl.query(ReceiveDelivery, one)2
INSERT INTO stock (item, quantity, deliveries) VALUES ($1, $2, 1)2
INSERT INTO stock (item, quantity, deliveries) VALUES ($1, $2, 1)3
ON CONFLICT (item) DO UPDATE SET3
ON CONFLICT (item) DO UPDATE SET4
quantity = stock.quantity + EXCLUDED.quantity,4
quantity = stock.quantity + excluded.quantity,5
deliveries = stock.deliveries + 15
deliveries = stock.deliveries + 16
RETURNING item, quantity, deliveries;6
RETURNING item, quantity, deliveries;AddItemidentical
TimescaleDB · db/queries/stock.sql
DuckDB · db/queries/stock.sql
1
-- sgl.query(AddItem, execrows)1
-- sgl.query(AddItem, execrows)2
INSERT INTO stock (item, quantity) VALUES ($1, 0)2
INSERT INTO stock (item, quantity) VALUES ($1, 0)3
ON CONFLICT (item) DO NOTHING;3
ON CONFLICT (item) DO NOTHING;ListStockidentical
TimescaleDB · db/queries/stock.sql
DuckDB · db/queries/stock.sql
1
-- sgl.query(ListStock, many)1
-- sgl.query(ListStock, many)2
SELECT item, quantity, deliveries FROM stock ORDER BY item;2
SELECT item, quantity, deliveries FROM stock ORDER BY item;What sgl generates
ReceiveDeliverydiffers
TimescaleDB
DuckDB
1
func (queries *Queries) ReceiveDelivery(ctx context.Context, params ReceiveDeliveryParams) (ReceiveDeliveryRow, error)1
func (queries *Queries) ReceiveDelivery(ctx context.Context, params ReceiveDeliveryParams) (ReceiveDeliveryRow, error)2
2
3
type ReceiveDeliveryParams struct {3
type ReceiveDeliveryParams struct {4
Item string4
Item string5
Quantity int645
Quantity int326
}6
}7
7
8
type ReceiveDeliveryRow struct {8
type ReceiveDeliveryRow struct {9
Item string `json:"item"`9
Item string `json:"item"`10
Quantity int64 `json:"quantity"`10
Quantity int32 `json:"quantity"`11
Deliveries int64 `json:"deliveries"`11
Deliveries int32 `json:"deliveries"`12
}12
}AddItemidentical
TimescaleDB
DuckDB
1
func (queries *Queries) AddItem(ctx context.Context, item string) (int64, error)1
func (queries *Queries) AddItem(ctx context.Context, item string) (int64, error)ListStockdiffers
TimescaleDB
DuckDB
1
func (queries *Queries) ListStock(ctx context.Context) ([]ListStockRow, error)1
func (queries *Queries) ListStock(ctx context.Context) ([]ListStockRow, error)2
2
3
type ListStockRow struct {3
type ListStockRow struct {4
Item string `json:"item"`4
Item string `json:"item"`5
Quantity int64 `json:"quantity"`5
Quantity int32 `json:"quantity"`6
Deliveries int64 `json:"deliveries"`6
Deliveries int32 `json:"deliveries"`7
}7
}The program
example.godiffers
TimescaleDB
DuckDB
1
package main1
package main2
2
3
import (3
import (4
"context"4
"context"5
"database/sql"5
"database/sql"6
"fmt"6
"fmt"7
"io"7
"io"8
8
9
"seagull.sh/seagull/examples/postgres/021_upserts/internal/store"9
"seagull.sh/seagull/examples/duckdb/021_upserts/internal/store"10
)10
)11
11
12
// run books three deliveries into the stock table, two of them for the same item, then12
// run books three deliveries into the stock table, two of them for the same item, then13
// adds two items only if they are new, and prints the stock that results.13
// adds two items only if they are new, and prints the stock that results.14
//14
//15
// Takes database (*sql.DB) which is a migrated database.15
// Takes database (*sql.DB) which is a migrated database.16
// Takes output (io.Writer) which receives each upsert's outcome and the final stock.16
// Takes output (io.Writer) which receives each upsert's outcome and the final stock.17
//17
//18
// Returns error when a query fails.18
// Returns error when a query fails.19
func run(ctx context.Context, database *sql.DB, output io.Writer) error {19
func run(ctx context.Context, database *sql.DB, output io.Writer) error {20
queries := store.New(database)20
queries := store.New(database)21
21
22
// ReceiveDelivery inserts a new item, or adds to the quantity of one already in stock.22
// ReceiveDelivery inserts a new item, or adds to the quantity of one already in stock.23
// EXCLUDED.quantity is the value the INSERT tried to write, so the parameters stay plain23
// excluded.quantity is the value the INSERT tried to write, so the parameters stay plain24
// Item and Quantity fields.24
// Item and Quantity fields.25
deliveries := []store.ReceiveDeliveryParams{25
deliveries := []store.ReceiveDeliveryParams{26
{Item: "cod", Quantity: 10},26
{Item: "cod", Quantity: 10},27
{Item: "potatoes", Quantity: 40},27
{Item: "potatoes", Quantity: 40},28
{Item: "cod", Quantity: 5},28
{Item: "cod", Quantity: 5},29
}29
}30
for _, delivery := range deliveries {30
for _, delivery := range deliveries {31
row, err := queries.ReceiveDelivery(ctx, delivery)31
row, err := queries.ReceiveDelivery(ctx, delivery)32
if err != nil {32
if err != nil {33
return fmt.Errorf("receiving %s: %w", delivery.Item, err)33
return fmt.Errorf("receiving %s: %w", delivery.Item, err)34
}34
}35
fmt.Fprintf(output, "%-8s delivery %d: +%d, now %d in stock\n",35
fmt.Fprintf(output, "%-8s delivery %d: +%d, now %d in stock\n",36
row.Item, row.Deliveries, delivery.Quantity, row.Quantity)36
row.Item, row.Deliveries, delivery.Quantity, row.Quantity)37
}37
}38
38
39
// AddItem uses DO NOTHING, and execrows reports whether the row went in: 1 for a new39
// AddItem uses DO NOTHING, and execrows reports whether the row went in: 1 for a new40
// item, 0 when the item was already there and the insert was skipped.40
// item, 0 when the item was already there and the insert was skipped.41
for _, item := range []string{"peas", "cod"} {41
for _, item := range []string{"peas", "cod"} {42
added, err := queries.AddItem(ctx, item)42
added, err := queries.AddItem(ctx, item)43
if err != nil {43
if err != nil {44
return fmt.Errorf("adding %s: %w", item, err)44
return fmt.Errorf("adding %s: %w", item, err)45
}45
}46
if added == 0 {46
if added == 0 {47
fmt.Fprintf(output, "%s is already stocked, nothing changed\n", item)47
fmt.Fprintf(output, "%s is already stocked, nothing changed\n", item)48
continue48
continue49
}49
}50
fmt.Fprintf(output, "added %s with no stock yet\n", item)50
fmt.Fprintf(output, "added %s with no stock yet\n", item)51
}51
}52
52
53
stock, err := queries.ListStock(ctx)53
stock, err := queries.ListStock(ctx)54
if err != nil {54
if err != nil {55
return fmt.Errorf("listing stock: %w", err)55
return fmt.Errorf("listing stock: %w", err)56
}56
}57
for _, row := range stock {57
for _, row := range stock {58
fmt.Fprintf(output, "%-8s %2d\n", row.Item, row.Quantity)58
fmt.Fprintf(output, "%-8s %2d\n", row.Item, row.Quantity)59
}59
}60
return nil60
return nil61
}61
}Go type differences
The same SQL types map to different Go types, because each database reports them differently.
| Query | Field | TimescaleDB | DuckDB |
|---|---|---|---|
| ReceiveDelivery | parameter quantity | int64 | int32 |
| ReceiveDelivery | column quantity | int64 | int32 |
| ReceiveDelivery | column deliveries | int64 | int32 |
| ListStock | column quantity | int64 | int32 |
| ListStock | column deliveries | int64 | int32 |