ClickHouse

问题 I want to use kafka integration for clickhouse. I tried to use official tutorial like here! All table has been created. I run kafka server. Next run kafka producer and write in command promt json object like row in database. Like this: {"timestamp":1554138000,"level":"first","message":"abc"} I checked kafka consumer.It received object. But when I cheked tables in my clickhouse database there were empty rows. Any ideas what I did wrong? 回答1: UPDATE To ignore malformed messages pass kafka_skip

问题 I can get data from the clickhouse database using get method, Similarly i want to insert data using post method . Is their anyway to do like that 回答1: Modification of data in HTTP interface is allowed using POST method only. Check out example given below on Clickhouse official documentation. echo 'INSERT INTO t VALUES (1),(2),(3)' | curl 'http://localhost:8123/' --data-binary @- https://clickhouse.yandex/docs/en/interfaces/http_interface/ Edit With Post Image. Screenshot of postman and

问题 For a table e.g. containing a date, price timeseries with prices every e.g. millisecond, how can this be downsampled into groups of open high low close (ohlc) rows with time interval e.g. minute? 回答1: While option with arrays will work, the simplest option here is to use use combination of group by timeintervals with min , max , argMin , argMax aggregate functions. SELECT id, minute, max(value) AS high, min(value) AS low, avg(value) AS avg, argMin(value, timestamp) AS first, argMax(value,

问题 For a table e.g. containing a date, price timeseries with prices every e.g. millisecond, how can this be downsampled into groups of open high low close (ohlc) rows with time interval e.g. minute? 回答1: While option with arrays will work, the simplest option here is to use use combination of group by timeintervals with min , max , argMin , argMax aggregate functions. SELECT id, minute, max(value) AS high, min(value) AS low, avg(value) AS avg, argMin(value, timestamp) AS first, argMax(value,

问题 I have connected to a clickhouse db with dbeaver and installed sqlalchemy v1.3.13 and clickhouse-sqlalchemy 0.1.3 for python 3.7. When I tried to connect with from sqlalchemy import create_engine engine_clickhouse = create_engine('clickhouse://use:pass@host:port/db') engine_clickhouse.raw_connection() I got Exception: Code: 516, e.displayText() = DB::Exception: default: Authentication failed: password is incorrect or there is no user with such name (version 20.3.4.10 (official build)) Does

问题 After installed the ClickHouse on Ubuntu 18.04.2 in Hyper-V VM, I use clickhouse-client inside the VM to connect, it works fine. I used the browser in Host PC to open http://127.27.16.11:8123, it shows ERR_CONNECTION_REFUSED error. Then I edit the /etc/clickhouse-server/config.xml and uncomment the 0.0.0.0 and restart the clickhouse-server. I refresh the browser and it shows OK status. However, when I use clickhouse-client inside the VM to connect server again, it prompts Connection refused.

问题 I am using Apache Beam to consume json and insert into clickhouse. I am currently having a problem with the Array data type. Everything works fine before I add an array type of field Schema.Field.of("inputs.value", Schema.FieldType.array(Schema.FieldType.INT64).withNullable(true)) Code for the transformations p.apply(transformNameSuffix + "ReadFromPubSub", PubsubIO.readStrings().fromSubscription(chainConfig.getPubSubSubscriptionPrefix() + "transactions").withIdAttribute(PUBSUB_ID_ATTRIBUTE))

问题 I want to insert data to ClickHouse per HTTP-interface from file. CSV, JSON, TabSeparated, it's doesn't matters. Or insert data to Docker-container uses yandex/clickhouse-server . Using HTTP-interface, for example: cat source.csv | curl 'http://localhost:8123/?query=INSERT INTO table FORMAT CSV' Using Docker-container, for example: docker run -it --rm --link some-clickhouse-server:clickhouse-server yandex/clickhouse-client --host clickhouse-server {THERE SOME OPTIONS ABOUT INSERT FROM FILE}

问题 I want to insert data to ClickHouse per HTTP-interface from file. CSV, JSON, TabSeparated, it's doesn't matters. Or insert data to Docker-container uses yandex/clickhouse-server . Using HTTP-interface, for example: cat source.csv | curl 'http://localhost:8123/?query=INSERT INTO table FORMAT CSV' Using Docker-container, for example: docker run -it --rm --link some-clickhouse-server:clickhouse-server yandex/clickhouse-client --host clickhouse-server {THERE SOME OPTIONS ABOUT INSERT FROM FILE}