func PrepareStatements(conn *pgx.Conn) error {
for name, sql := range preparedStatements {
if _, err := conn.Prepare(name, sql); err != nil {
return err
}
}
return nil
}
func mustPrepare(t testing.TB, conn *pgx.Conn, name, sql string) *pgx.PreparedStatement {
ps, err := conn.Prepare(name, sql)
if err != nil {
t.Fatalf("Could not prepare %v: %v", name, err)
}
return ps
}
func benchmarkSelectWithLog(b *testing.B, conn *pgx.Conn) {
_, err := conn.Prepare("test", "select 1::int4, 'johnsmith', '*****@*****.**', 'John Smith', 'male', '1970-01-01'::date, '2015-01-01 00:00:00'::timestamptz")
if err != nil {
b.Fatal(err)
}
b.ResetTimer()
for i := 0; i < b.N; i++ {
var record struct {
id int32
userName string
email string
name string
sex string
birthDate time.Time
lastLoginTime time.Time
}
err = conn.QueryRow("test").Scan(
&record.id,
&record.userName,
&record.email,
&record.name,
&record.sex,
&record.birthDate,
&record.lastLoginTime,
)
if err != nil {
b.Fatal(err)
}
// These checks both ensure that the correct data was returned
// and provide a benchmark of accessing the returned values.
if record.id != 1 {
b.Fatalf("bad value for id: %v", record.id)
}
if record.userName != "johnsmith" {
b.Fatalf("bad value for userName: %v", record.userName)
}
if record.email != "*****@*****.**" {
b.Fatalf("bad value for email: %v", record.email)
}
if record.name != "John Smith" {
b.Fatalf("bad value for name: %v", record.name)
}
if record.sex != "male" {
b.Fatalf("bad value for sex: %v", record.sex)
}
if record.birthDate != time.Date(1970, 1, 1, 0, 0, 0, 0, time.Local) {
b.Fatalf("bad value for birthDate: %v", record.birthDate)
}
if record.lastLoginTime != time.Date(2015, 1, 1, 0, 0, 0, 0, time.Local) {
b.Fatalf("bad value for lastLoginTime: %v", record.lastLoginTime)
}
}
}
// afterConnect creates the prepared statements that this application uses
func afterConnect(conn *pgx.Conn) (err error) {
_, err = conn.Prepare("getUrl", `
select url from shortened_urls where id=$1
`)
if err != nil {
return
}
_, err = conn.Prepare("deleteUrl", `
delete from shortened_urls where id=$1
`)
if err != nil {
return
}
// There technically is a small race condition in doing an upsert with a CTE
// where one of two simultaneous requests to the shortened URL would fail
// with a unique index violation. As the point of this demo is pgx usage and
// not how to perfectly upsert in PostgreSQL it is deemed acceptable.
_, err = conn.Prepare("putUrl", `
with upsert as (
update shortened_urls
set url=$2
where id=$1
returning *
)
insert into shortened_urls(id, url)
select $1, $2 where not exists(select 1 from upsert)
`)
return
}