mirror of https://github.com/jackc/pgx.git
Add examples
Jack Christensen
parent
9a61fc250f
commit
68b7e12df2
136
rows_test.go
136
rows_test.go
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@ -6,6 +6,7 @@ import (
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"fmt"
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"os"
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"testing"
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"time"
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"github.com/jackc/pgx/v5"
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"github.com/jackc/pgx/v5/pgconn"
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@ -147,6 +148,35 @@ func TestCollectRows(t *testing.T) {
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})
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}
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// This example uses CollectRows with a manually written collector function. In most cases RowTo, RowToAddrOf,
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// RowToStructByPos, RowToAddrOfStructByPos, or another generic function would be used.
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func ExampleCollectRows() {
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ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
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defer cancel()
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conn, err := pgx.Connect(ctx, os.Getenv("PGX_TEST_DATABASE"))
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if err != nil {
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fmt.Printf("Unable to establish connection: %v", err)
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return
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}
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rows, _ := conn.Query(ctx, `select n from generate_series(1, 5) n`)
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numbers, err := pgx.CollectRows(rows, func(row pgx.CollectableRow) (int32, error) {
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var n int32
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err := row.Scan(&n)
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return n, err
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})
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if err != nil {
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fmt.Printf("CollectRows error: %v", err)
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return
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}
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fmt.Println(numbers)
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// Output:
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// [1 2 3 4 5]
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}
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func TestCollectOneRow(t *testing.T) {
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defaultConnTestRunner.RunTest(context.Background(), t, func(ctx context.Context, t testing.TB, conn *pgx.Conn) {
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rows, _ := conn.Query(ctx, `select 42`)
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@ -201,6 +231,29 @@ func TestRowTo(t *testing.T) {
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})
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}
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func ExampleRowTo() {
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ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
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defer cancel()
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conn, err := pgx.Connect(ctx, os.Getenv("PGX_TEST_DATABASE"))
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if err != nil {
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fmt.Printf("Unable to establish connection: %v", err)
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return
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}
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rows, _ := conn.Query(ctx, `select n from generate_series(1, 5) n`)
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numbers, err := pgx.CollectRows(rows, pgx.RowTo[int32])
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if err != nil {
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fmt.Printf("CollectRows error: %v", err)
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return
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}
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fmt.Println(numbers)
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// Output:
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// [1 2 3 4 5]
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}
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func TestRowToAddrOf(t *testing.T) {
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defaultConnTestRunner.RunTest(context.Background(), t, func(ctx context.Context, t testing.TB, conn *pgx.Conn) {
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rows, _ := conn.Query(ctx, `select n from generate_series(0, 99) n`)
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@ -214,6 +267,35 @@ func TestRowToAddrOf(t *testing.T) {
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})
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}
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func ExampleRowToAddrOf() {
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ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
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defer cancel()
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conn, err := pgx.Connect(ctx, os.Getenv("PGX_TEST_DATABASE"))
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if err != nil {
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fmt.Printf("Unable to establish connection: %v", err)
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return
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}
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rows, _ := conn.Query(ctx, `select n from generate_series(1, 5) n`)
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pNumbers, err := pgx.CollectRows(rows, pgx.RowToAddrOf[int32])
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if err != nil {
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fmt.Printf("CollectRows error: %v", err)
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return
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}
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for _, p := range pNumbers {
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fmt.Println(*p)
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}
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// Output:
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// 1
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// 2
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// 3
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// 4
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// 5
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}
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func TestRowToMap(t *testing.T) {
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defaultConnTestRunner.RunTest(context.Background(), t, func(ctx context.Context, t testing.TB, conn *pgx.Conn) {
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rows, _ := conn.Query(ctx, `select 'Joe' as name, n as age from generate_series(0, 9) n`)
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@ -228,7 +310,7 @@ func TestRowToMap(t *testing.T) {
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})
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}
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func TestRowToStructPos(t *testing.T) {
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func TestRowToStructByPos(t *testing.T) {
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type person struct {
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Name string
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Age int32
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@ -247,6 +329,58 @@ func TestRowToStructPos(t *testing.T) {
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})
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}
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func ExampleRowToStructByPos() {
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ctx, cancel := context.WithTimeout(context.Background(), 15*time.Second)
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defer cancel()
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conn, err := pgx.Connect(ctx, os.Getenv("PGX_TEST_DATABASE"))
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if err != nil {
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fmt.Printf("Unable to establish connection: %v", err)
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return
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}
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// Setup example schema and data.
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_, err = conn.Exec(ctx, `
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create temporary table products (
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id int primary key generated by default as identity,
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name varchar(100) not null,
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price int not null
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);
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insert into products (name, price) values
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('Cheeseburger', 10),
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('Double Cheeseburger', 14),
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('Fries', 5),
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('Soft Drink', 3);
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`)
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if err != nil {
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fmt.Printf("Unable to setup example schema and data: %v", err)
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return
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}
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type product struct {
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ID int32
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Name string
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Price int32
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}
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rows, _ := conn.Query(ctx, "select * from products where price < $1 order by price desc", 12)
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products, err := pgx.CollectRows(rows, pgx.RowToStructByPos[product])
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if err != nil {
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fmt.Printf("CollectRows error: %v", err)
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return
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}
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for _, p := range products {
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fmt.Printf("%s: $%d\n", p.Name, p.Price)
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}
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// Output:
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// Cheeseburger: $10
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// Fries: $5
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// Soft Drink: $3
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}
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func TestRowToAddrOfStructPos(t *testing.T) {
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type person struct {
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Name string
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