clickhouse-java
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ClickHouse
Java client and JDBC driver for ClickHouse
Problem: when data is read from stream it automatically decoded in most suitable form. It works well except with strings because it create overhead. Solution: - store string as `byte[]`...
### Summary After migrating from the ClickHouse Java client v1 to v2 we observed a major performance regression: more than 2 times less throughput. We use ClickHouse as a pre-aggregation...
### Use case Download binary files from CH ### Describe the solution you'd like Implement 1. Class - ResultSetImpl Method - getBinaryStream(String columnLabel) 2. Class - ResultSetImpl Method - getBlob(String...
### Describe your feedback I’m currently working on upgrading the ClickHouse client in Trino from version 0.7.1-patch1 to 0.9.2 [#26735](https://github.com/trinodb/trino/pull/26735). In the Trino ClickHouse connector, we rely on ClickHouseClientOption.USE_BINARY_STRING. However,...
## Description ### Steps to reproduce 1. Create the following table: ```sql CREATE TABLE default.example_table ( `id` Int32, `name` String ) ENGINE = MergeTree ORDER BY id SETTINGS index_granularity =...
### Describe your feedback when you pass a very large number (larger than max long, but smaller than max UInt64) as a string in a simple insert, the client attempts...
**Description** When setQueryTimeout() is applied to a PreparedStatement, the timeout is not honored during query execution. Even if the query exceeds the configured timeout value, it continues to run until...
### Describe the bug I tried to select hash in both tsv and row binary formats and got unexpected behaviour: 1. asString() returns same value for both query as expected...
```sql select sum(number), greater from (select number, number > 5 as greater from numbers(10)) group by greater with totals ``` ClickHouse 22.8.19.10 / ClickHouse JDBC Driver 0.4.6 (revision: dd91e17) --...
Currently, only [groupBitmap](https://clickhouse.com/docs/en/sql-reference/aggregate-functions/reference/groupbitmap) is [supported](https://github.com/ClickHouse/clickhouse-java/blob/d175cd7d0e8f0427a8e2bc1b20c597990cd507b4/clickhouse-data/src/main/java/com/clickhouse/data/format/ClickHouseRowBinaryProcessor.java#L510-L515) as parameter for a table column of type [AggregateFunction](https://clickhouse.com/docs/en/sql-reference/data-types/aggregatefunction/). It would be good if [all](https://clickhouse.com/docs/en/sql-reference/aggregate-functions/reference/) aggregate functions are supported.
