Golang SQL database driver for Yandex ClickHouse
- Uses native ClickHouse tcp client-server protocol
- Compatibility with
database/sql - Round Robin load-balancing
- Bulk write support :
begin->prepare->(in loop exec)->commit
- username/password - auth credentials
- database - select the current default database
- read_timeout/write_timeout - timeout in second
- no_delay - disable/enable the Nagle Algorithm for tcp socket (default is 'true' - disable)
- alt_hosts - comma separated list of single address host for load-balancing
- connection_open_strategy - random/in_order (default random).
- random - choose random server from set
- in_order - first live server is choosen in specified order
- block_size - maximum rows in block (default is 1000000). If the rows are larger then the data will be split into several blocks to send them to the server
- debug - enable debug output (boolean value)
SSL/TLS parameters:
- secure - establish secure connection (default is false)
- skip_verify - skip certificate verification (default is true)
example:
tcp://host1:9000?username=user&password=qwerty&database=clicks&read_timeout=10&write_timeout=20&alt_hosts=host2:9000,host3:9000
- UInt8, UInt16, UInt32, UInt64, Int8, Int16, Int32, Int64
- Float32, Float64
- String
- FixedString(N)
- Date
- DateTime
- Enum
- UUID
- Nullable(T)
- Array(T) (one-dimensional) godoc
- Compression
go get -u github.com/kshvakov/clickhouse
package main
import (
"database/sql"
"fmt"
"log"
"time"
"github.com/kshvakov/clickhouse"
)
func main() {
connect, err := sql.Open("clickhouse", "tcp://127.0.0.1:9000?debug=true")
if err != nil {
log.Fatal(err)
}
if err := connect.Ping(); err != nil {
if exception, ok := err.(*clickhouse.Exception); ok {
fmt.Printf("[%d] %s \n%s\n", exception.Code, exception.Message, exception.StackTrace)
} else {
fmt.Println(err)
}
return
}
_, err = connect.Exec(`
CREATE TABLE IF NOT EXISTS example (
country_code FixedString(2),
os_id UInt8,
browser_id UInt8,
categories Array(Int16),
action_day Date,
action_time DateTime
) engine=Memory
`)
if err != nil {
log.Fatal(err)
}
var (
tx, _ = connect.Begin()
stmt, _ = tx.Prepare("INSERT INTO example (country_code, os_id, browser_id, categories, action_day, action_time) VALUES (?, ?, ?, ?, ?, ?)")
)
defer stmt.Close()
for i := 0; i < 100; i++ {
if _, err := stmt.Exec(
"RU",
10+i,
100+i,
clickhouse.Array([]int16{1, 2, 3}),
time.Now(),
time.Now(),
); err != nil {
log.Fatal(err)
}
}
if err := tx.Commit(); err != nil {
log.Fatal(err)
}
rows, err := connect.Query("SELECT country_code, os_id, browser_id, categories, action_day, action_time FROM example")
if err != nil {
log.Fatal(err)
}
defer rows.Close()
for rows.Next() {
var (
country string
os, browser uint8
categories []int16
actionDay, actionTime time.Time
)
if err := rows.Scan(&country, &os, &browser, &categories, &actionDay, &actionTime); err != nil {
log.Fatal(err)
}
log.Printf("country: %s, os: %d, browser: %d, categories: %v, action_day: %s, action_time: %s", country, os, browser, categories, actionDay, actionTime)
}
if _, err := connect.Exec("DROP TABLE example"); err != nil {
log.Fatal(err)
}
}Use sqlx
package main
import (
"log"
"time"
"github.com/jmoiron/sqlx"
_ "github.com/kshvakov/clickhouse"
)
func main() {
connect, err := sqlx.Open("clickhouse", "tcp://127.0.0.1:9000?debug=true")
if err != nil {
log.Fatal(err)
}
var items []struct {
CountryCode string `db:"country_code"`
OsID uint8 `db:"os_id"`
BrowserID uint8 `db:"browser_id"`
Categories []int16 `db:"categories"`
ActionTime time.Time `db:"action_time"`
}
if err := connect.Select(&items, "SELECT country_code, os_id, browser_id, categories, action_time FROM example"); err != nil {
log.Fatal(err)
}
for _, item := range items {
log.Printf("country: %s, os: %d, browser: %d, categories: %v, action_time: %s", item.CountryCode, item.OsID, item.BrowserID, item.Categories, item.ActionTime)
}
}