Crate v_clickhouse_rs
source ·Expand description
§clickhouse-rs
Asynchronous Yandex ClickHouse client library for rust programming language.
§Installation
Library hosted on crates.io.
[dependencies]
clickhouse-rs = "*"
§Supported data types
- Date
- DateTime
- Decimal(P, S)
- Float32, Float64
- String, FixedString(N)
- UInt8, UInt16, UInt32, UInt64, Int8, Int16, Int32, Int64
- Nullable(T)
- Array(UInt/Int/String/Date/DateTime)
- IPv4/IPv6
- UUID
§DNS
schema://user:password@host[:port]/database?param1=value1&...¶mN=valueN
parameters:
-
compression
- Whether or not use compression (defaults tonone
). Possible choices:none
lz4
-
readonly
- Restricts permissions for read data, write data and change settings queries. (defaults tonone
). Possible choices:0
- All queries are allowed.1
- Only read data queries are allowed.2
- Read data and change settings queries are allowed.
-
connection_timeout
- Timeout for connection (defaults to500 ms
) -
keepalive
- TCP keep alive timeout in milliseconds. -
nodelay
- Whether to enableTCP_NODELAY
(defaults totrue
). -
pool_min
- Lower bound of opened connections forPool
(defaults to10
). -
pool_max
- Upper bound of opened connections forPool
(defaults to20
). -
ping_before_query
- Ping server every time before execute any query. (defaults totrue
). -
send_retries
- Count of retry to send request to server. (defaults to3
). -
retry_timeout
- Amount of time to wait before next retry. (defaults to5 sec
). -
ping_timeout
- Timeout for ping (defaults to500 ms
). -
alt_hosts
- Comma separated list of single address host for load-balancing.
example:
tcp://user:password@host:9000/clicks?compression=lz4&ping_timeout=42ms
§Optional features
clickhouse-rs
puts some functionality behind optional features to optimize compile time
for the most common use cases. The following features are available.
tokio_io
(enabled by default) — I/O based on Tokio.async_std
— I/O based on async-std (doesn’t work together withtokio_io
).tls
— TLS support (allowed only withtokio_io
).
§Example
use clickhouse_rs::{Block, Pool, errors::Error};
#[tokio::main]
async fn main() -> Result<(), Error> {
let ddl = r"
CREATE TABLE IF NOT EXISTS payment (
customer_id UInt32,
amount UInt32,
account_name Nullable(FixedString(3))
) Engine=Memory";
let block = Block::new()
.column("customer_id", vec![1_u32, 3, 5, 7, 9])
.column("amount", vec![2_u32, 4, 6, 8, 10])
.column("account_name", vec![Some("foo"), None, None, None, Some("bar")]);
let pool = Pool::new(database_url);
let mut client = pool.get_handle().await?;
client.execute(ddl).await?;
client.insert("payment", block).await?;
let block = client.query("SELECT * FROM payment").fetch_all().await?;
for row in block.rows() {
let id: u32 = row.get("customer_id")?;
let amount: u32 = row.get("amount")?;
let name: Option<&str> = row.get("account_name")?;
println!("Found payment {}: {} {:?}", id, amount, name);
}
Ok(())
}
Re-exports§
Modules§
- Error types.
- Pool types.
- Clickhouse types.
Macros§
- This macro is a convenient way to pass row into a block.
Structs§
- Represents Clickhouse Block
- Clickhouse client handle.