Closes #

Describe your proposed changes here.

• [ ] Well-formatted commit messages
• [ ] Tests pass
• [ ] Documentation updated or issue created (provide link to issue/pr)
• [ ] Signed CLA (if not already signed)

Is your feature request related to a problem? Please describe. Compaction Algorithm in CnosDB is like a box of chocolates. You never know what you're gonna get... kidding Nevertheless, Compaction Algorithm is still a black box to us and we would like to configure it based on our own understanding of dataset.

Describe the solution you'd like Similar to commercial version of Cassandra here, we could have WITH compaction keyword:

1. Disable compaction via CREATE SQL: CREATE TABLE DEMO(...) WITH compaction= { 'enabled' : false };
2. Enable compaction via CREATE SQL: CREATE TABLE DEMO(...) WITH compaction= { 'class' : 'LZ4Compressor' };
3. Disable compaction via ALTER TABLE SQL: ALTER TABLE DEMO WITH compaction= { 'enabled' : false };
4. Enable compaction via ALTER TABLE SQL: ALTER TABLE DEMO WITH compaction ={ 'class' : 'LZ4Compressor' }; ALTER TABLE DEMO WITH compaction ={ 'class' : 'DeflateCompressor', 'chunk_length_in_kb' : 64 };

Or you could try MariaDB way, using COMMENT keyword here:

1. Set Global Compaction Type in configuration file: columnstore_compression_type=LZ4
2. Set Table Compaction Type in SQL's COMMENT: CREATE TABLE DEMO(...) COMMENT 'compression=3';
3. Set Column Compaction Type in SQL's COMMENT:

CREATE TABLE DEMO(
    invoice_id BIGINT UNSIGNED NOT NULL,
    invoice_total DECIMAL(13, 2) COMMENT 'compression=3',
);

Describe alternatives you've considered We could disable compaction once for all in the configuration instead of DDL but DDL provides more granular way.

Additional context More granularity should be provided as well:

1. Global
2. Database
3. Table

This feature should be integrated in the cloud version as well.

Other alternatives:

1. TecentCloud's COMPRESSED keyword: https://www.tencentcloud.com/document/product/236/43480
2. ClickHouse's CODEC keyword: https://clickhouse.com/docs/en/sql-reference/statements/create/table#column-compression-codecs

Is your feature request related to a problem? Please describe. support those schema query statements

• [x] DESCRIBE DATABASE db_name;
• [x] DESCRIBE TABLE [db_name.] table_name;
• [x] SHOW DATABASES;
• [x] SHOW TABLES [ON <db_name>];
• [x] SHOW SERIES [ON <db_name>] FROM table_name [WHERE <tag_key> [ '<tag_value>' | ]] [LIMIT_clause]
• [x] SHOW TAG VALUES [ON <db_name>] FROM table_name WITH KEY [ [ "<tag_key>" | <regular_expression>] | [IN (""] [WHERE <tag_key> ['<tag_value>' | ]] [LIMIT_clause]

Errors inside the [run_wal_job,run_flush_job,run_compact_job,run_summary_job] functions are passed up

避免以上四个函数中的错误在内部消耗而外部不可知而向上传递,并将方法改为异步函数形式,另外项目Error设计不是很优雅

Hello, in docs/get-started.md document in the last step git clone https://github.com/cnosdb/cnosdb-isipho.git && cd cnosdb-isipho following address I can not pull, and then I pulled https://github. com/cnosdb/cnosdb.git, cargo build and then run the error as follows Can you tell me what the cause is?

Chinese original: 您好，在docs/get-started.md文档中最后一步git clone https://github.com/cnosdb/cnosdb-isipho.git && cd cnosdb-isipho如下地址我无法拉取，而后我拉取了https://github.com/cnosdb/cnosdb.git，cargo build后运行报错如下 方便问一下大概是什么原因嘛

Describe the bug parallel kvcore test will panic，we add serial for each test，the test will pass

To Reproduce cargo test --package tskv --lib kvcore::test

Expected behavior should parallel

Additional context none

Closes #

Describe your proposed changes here.

• [x] Well-formatted commit messages
• [ ] Tests pass
• [ ] Documentation updated or issue created (provide link to issue/pr)
• [x] Signed CLA (if not already signed)

Describe the bug.

RewriteRegexConditions can panic when given an invalid regex, e.g.

select * from cpu where ( host =~ /foo/ ^ other AND env =~ /bar/ ) and time >= now()-15m

Gives a panic:

panic:interface conversion: cnosql.Expr is *cnosql.BinaryExpr, not *cnosql.RegexLiteral

This should return an error without panic'ing

Describe the bug the latest branch compile error in my machine.

Arch Linux 6.1.1 x86_64
rustc version 1.64.0
cargo version: 1.64.0

cargo ouput:

Caused by:
  process didn't exit successfully: `/home/fanr/Github/cnosdb/target/debug/build/protos-98787f2df9789b3c/build-script-build` (exit status: 101)
  --- stderr
  thread 'main' panicked at 'Failed to generate file 'models.rs' by flatc(path: 'flatc'): Os { code: 2, kind: NotFound, message: "No such file or directory" }.', common/protos/build.rs:123:21
  stack backtrace:
     0: rust_begin_unwind
               at /rustc/a55dd71d5fb0ec5a6a3a9e8c27b2127ba491ce52/library/std/src/panicking.rs:584:5
     1: core::panicking::panic_fmt
               at /rustc/a55dd71d5fb0ec5a6a3a9e8c27b2127ba491ce52/library/core/src/panicking.rs:142:14
     2: build_script_build::main::{{closure}}
               at ./build.rs:123:21
     3: core::result::Result<T,E>::unwrap_or_else
               at /rustc/a55dd71d5fb0ec5a6a3a9e8c27b2127ba491ce52/library/core/src/result.rs:1493:23
     4: build_script_build::main
               at ./build.rs:111:26
     5: core::ops::function::FnOnce::call_once
               at /rustc/a55dd71d5fb0ec5a6a3a9e8c27b2127ba491ce52/library/core/src/ops/function.rs:248:5
  note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.
warning: build failed, waiting for other jobs to finish...

To Reproduce Steps to reproduce the behavior:

Expected behavior A clear and concise description of what you expected to happen.

Additional context Add any other context about the problem here.

compile the cnosdb following the get-started page: error reported: type Scalar is not a member of trait flatbuffers::EndianScalar --> common/protos/src/generated/flatbuffers_generated/models.rs:106:9 | 106 | type Scalar = i32; | ^^^^^^^^^^^^^^^^^^ not a member of trait flatbuffers::EndianScalar

Parsing lineprotocol may have performance issues. There are the following optimization measures. 1.Use the nom library for parsing 2.Add some error messages. 3.Use smallvec that allocates memory on the stack

Now using our optimization rules implicit_type_conversion throws a datafusion internal error. We need to improve this error message

sql

explain select time from test_double_conv where fa >= '1997-01-31';

response

422 Unprocessable Entity
{"error_code":"010000","error_message":"Datafusion: Internal error: Optimizer rule 'implicit_type_conversion' failed due to unexpected error: Arrow error: Cast error: Cannot cast string '1997-01-31' to value of Float64 type. This was likely caused by a bug in DataFusion's code and we would welcome that you file an bug report in our issue tracker"}

Is your feature request related to a problem? Please describe. A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]

Describe the solution you'd like Implement TagScan support for Coodinator Service

Describe alternatives you've considered A clear and concise description of any alternative solutions or features you've considered.

Additional context Add any other context or screenshots about the feature request here.

Is your feature request related to a problem? Please describe. A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]

Describe the solution you'd like SQL command

• [ ] Move Vnode [vnode_id] to Node [node_id]
• [ ] Copy Vnode [vnode_id] to Node [node_id]
• [ ] Drop Vnode [vnode_id]
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Additional context Add any other context or screenshots about the feature request here.

Is your feature request related to a problem? Please describe. When reading a file, spend a lot of time opening the file and reading the index from disk Describe the solution you'd like Add lru cache module for our column file to improve query

Describe alternatives you've considered A clear and concise description of any alternative solutions or features you've considered.

Additional context Add any other context or screenshots about the feature request here.

Since 2019, "AI for Systems and Systems for AI" has become a trend.

As we all know, TensorFlow and PyTorch are the most popular AI frameworks nowadays.

However, I have noticed that CnosDB does not yet support a Python API, which could potentially lead to a loss of users such as data scientists and data engineers.

In contrast, InfluxDB, a competitor of CnosDB, released the first version of a Python Client for interacting with InfluxDB in 2013. (Reference: https://github.com/influxdata/influxdb-python).

I believe it is time for CnosDB to support a Python API.