skytable/CHANGELOG.md

# Changelog

All changes in this project will be noted in this file.

## Unreleased

### Additions

- `skyd`:
  - Pipelined queries are now supported
  - The `whereami` action was added which lets one find out which entity the current connection
    is connected to
- `skysh`:
  - now shows the current entity in the prompt
  - handles special character strings more reliably
  - now supports splitting a command across multiple lines
  - now supports multi-line pastes
  - now supports comments (beginning with `#`)

## Version 0.7.1

### Additions

- Added the list data type
- Added actions for lists:
  - `LSET <list> <values> ...`
  - `LGET`
    - `LGET <list>`
    - `LGET <list> LEN`
    - `LGET <list> VALUEAT <idx>`
    - `LGET <list> LIMIT <limit>`
    - `LGET <list> FIRST`
    - `LGET <list> LAST`
  - `LMOD`
    - `LMOD <list> push <value>`
    - `LMOD <list> insert <index> <value>`
    - `LMOD <list> pop <optional index>`
    - `LMOD <list> remove <index>`
    - `LMOD <list> clear`
- Added creation of lists:
  - `CREATE TABLE <entity> keymap(type,list<type>)`
- Added compatibility of `DEL`, `EXISTS` and `LSKEYS` with lists
- Added support for configuration via environment variables

### Improvements

- Reduced memory usage in `sky-bench`
- Reduced allocations in Skyhash (`skyd`) protocol implementation
- Misc. fixes in internal structures (`skyd`)
- Improvements in printing of binary strings in `skysh`

### Fixes

- Fixed unexpected removal of single and double quotes from input strings in `skysh`
- Fixed incorrect removal of quotes from input strings in `skysh`

## Version 0.7.0

### Additions

- **Multiple keyspaces**:
  - Keyspaces hold multiple tables and determine the replication strategy
  - Keyspaces can be created with:
    ```sql
    CREATE KEYSPACE <name>
    ```
  - The `system` keyspace is reserved for the system while the `default` keyspace is
    the one available by default. The `system` or `default` keyspace cannot be removed
  - Keyspaces can be deleted with:
    ```sql
    DROP KEYSPACE <name>
    ```
  - If a keyspace still has tables, it cannot be dropped by using `DROP KEYSPACE <name>`, instead
    one needs to use `DROP KEYSPACE <name> force` to force drop the keyspace
- **Multiple tables**:
  - Tables hold the actual data. When you connect to the server, you are connected to the `default`
    table in the `default` keyspace. This table is non-removable
  - Tables can be created with:
    ```sql
    CREATE TABLE <entity> <model>(modelargs) <properties>
    ```
  - Tables can be dropped with:
    ```sql
    DROP TABLE <entity>
    ```
- **Entity groups**: While using DDL queries and inspection queries, we can use the _Fully Qualified Entity_ (FQE) syntax instead of the table name. For example, to `inspect` the `cyan` table in keyspace `supercyan`, one can simply run:
  ```sql
  INSPECT TABLE supercyan:cyan
  ```
  The syntax is:
  ```sql
  keyspace:table
  ```
  **Note**: Both keyspaces and tables are entities. The names of entities must:
  - Begin with an underscore (\_) or an ASCII alphabet
  - Not begin with a number (0-9)
  - Must have lesser than 64 characters
- **Keymap data model**:
  - To create a keymap table, run:
    ```sql
    CREATE TABLE <entity> keymap(<type>,<type>)
    ```
  - The following types were introduced:
    - `str`: A valid unicode string
    - `binstr`: A binary string
- **Volatile table property**:

  - To create a volatile table, irrespective of the data model, run:
    ```sql
    CREATE TABLE <entity> <model>(modelargs) volatile
    ```
  - Volatile tables always exist, but the data in them does not persist between restarts. This makes them extremely useful for caches

- **Inspection**:
  - Keyspaces can be inspected with:
    ```sql
    INSPECT KEYSPACE <name>
    ```
    This will list all the tables in the keyspace
  - Tables can be inspected with:
    ```sql
    INSPECT TABLE <entity>
    ```
    This will give information about the data model and other properties of the table
  - To list all keyspaces, this can be run:
    ```sql
    INSPECT KEYSPACES
    ```
- **Cyanstore 1A disk storage format**: Cyanstore (v1A) was a new storage format built for the multi-keyspace-table world. It efficiently stores and retrieves records, tables and keyspaces
- **Realtime keyspace/table switch**
  - To switch to a new keyspace in real-time, one needs to run:
    ```sql
    USE keyspace
    ```
  - To switch to a new table in real-time, one needs to run:
    ```sql
    USE keyspace:table
    ```
- **Entity respecting actions**:

  - **`FLUSHDB`**: To flush all the data in a specific table, run:
    ```sql
    FLUSHDB <entity>
    ```
  - **`DBSIZE`**: To see the number of entries in a specific table, run:
    ```sql
    DBSIZE <entity>
    ```
  - **`LSKEYS`**:
    - `LSKEYS` will return keys from the current table
    - `LSKEYS <count>` will return _count_ keys from the current table
    - `LSKEYS <entity>` will return keys from the given table
    - `LSKEYS <entity> <count>` will return _count_ keys from the given table

- **Snapshot isolation for strong actions**: This makes strong actions
  extremely reliable when compared to the earlier releases
- Non-interactive TLS private key passphrase input: Just save your password in some
  file and then pass `--tlspassin /path/to/passfile.txt`. You can do the same by using the
  `tlspassin` key under SSL in the configuration file
- `MPOP` now replaces `POP` to accept multiple keys while `POP` will accept a single key
  to follow the `MGET`/`GET` naming convention
- TLS port can now be set to a custom port via CLI arguments
- `sky-bench` can now run multiple times to get average values through the `--runs` option
- `HEYA` now does an echo with the second argument

### Fixes

- Zero length argument causing runtime panic in `skysh`
- `HEYA!` not reporting errors on incorrect number of arguments
- Panic on incorrect data type in `skyd`
- `sky-bench` no longer affects your personal data because it creates a random temporary table
  under the `default` keyspace
- `sky-bench`'s `testkey` subcommand causing key collisions
- Fix log output in `sky-bench` even if the `--json` flag was passed
- Use flocks to enable auto release of pid file, even if process is forcefully terminated
- Fixes [CVE-2021-37625](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37625)

### Breaking

- All actions now accept the `AnyArray` type introduced in Skyhash 1.1
- `POP` now accepts one key while `MPOP` accepts multiple keys
- Disk storage format has changed

## Version 0.6.4 [2021-08-05]

### Fixes

- Fixes [CVE-2021-37625](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-37625) (backport)

## Version 0.6.3 [2021-06-27]

### Additions

- The maximum number of clients can now be manually configured [see [#182](https://github.com/skytable/skytable/pull/182)]

### Fixes

- Ability to connect to the server over TLS has been restored in `skysh` [see [#181](https://github.com/skytable/skytable/pull/181)]

## Version 0.6.2 [2021-06-24]

### Fixes

- The save operation now automatically attempts to recover on failure during termination [see [#166](https://github.com/skytable/skytable/pull/166)]
- More than one process can no longer concurrently use the same data directory, preventing any possible data corruption [see [#169](https://github.com/skytable/skytable/pull/169), [#167](https://github.com/skytable/skytable/issues/167)]
- Fixed longstanding error in `sky-bench` component that caused key collisions
- Fixed bug in `sky-bench` that allowed passing 0 for the inputs
- Fixed handling of SIGTERM in `skyd` [see [#178](https://github.com/skytable/skytable/pull/178)]
- Fixed incorrect termination codes [see [#178](https://github.com/skytable/skytable/pull/178)]

### Additions

- Added the `POP` query [[see #173](https://github.com/skytable/skytable/pull/173)]
- Added stress testing for testing correctness under load [[see #175](https://github.com/skytable/skytable/pull/175)]

### Workflow

- Use Makefiles for builds [see [#172](https://github.com/skytable/skytable/pull/172), [#174](https://github.com/skytable/skytable/pull/174)]
- Tier-1 Support for ARM64 [see [#179](https://github.com/skytable/skytable/pull/179)]

## Version 0.6.1 [2021-06-07]

> No breaking changes

- Snapshotting failure will now poison the database (customizable through CLI options or the configuration file)
  [see [#160](https://github.com/skytable/skytable/pull/160)]
- Added file-locking on Solaris [see [#162](https://github.com/skytable/skytable/pull/162)]
- Fixed missing explicit `fsync` or `FlushFileBuffers` after writing data
- Optimized wait on snapshot busy-loop using `_mm_pause` (on x86/x86_64) or `__yield` (on aarch64/arm)

## Version 0.6.0 [2021-05-27]

> Breaking changes!

- ⚠ Dropped support for Terrapipe 1.0 (reached EOL)
- ⚠ New disk storage format with much faster reads and/or writes
- Added support for Skyhash 1.0 (see [#147](https://github.com/skytable/skytable/pull/147))
- Fixed persistence bugs (see [#151](https://github.com/skytable/skytable/pull/151))
- Fixed bugs in background services (see [#152](https://github.com/skytable/skytable/pull/152))
- Make BGSAVE recoverable (see [#153](https://github.com/skytable/skytable/pull/153))
- Added `lskeys` action (see [#155](https://github.com/skytable/skytable/pull/155))
- Added `compat` module (see [#158](https://github.com/skytable/skytable/pull/158))
- Added backward compatibility for storage formats all the way upto 0.3.0. See [this wiki article](https://github.com/skytable/skytable/wiki/Disk-storage-formats) for more information

### Upgrading existing clients

As Terrapipe 1.0 has reached EOL, all clients have to be upgraded to use the [Skyhash 1.0 Protocol](https://docs.skytable.io/protocol/skyhash).

### Upgrading existing datasets

Please refer to [this wiki article](https://github.com/skytable/skytable/wiki/Disk-storage-formats).

### Improvements in the new protocol (Skyhash)

- Upto 40% lower bandwidth requirements
- Upto 30% faster queries
- Support for recursive arrays
- More robust and well tested than Terrapipe

### Internal codebase improvements

- BGSAVE is now tested by the test suite
- `skysh` and `sky-bench` both use the [Rust client driver for Skytable](https://github.com/skytable/client-rust).

## Version 0.5.3 [2021-05-13]

> No breaking changes

Fix persistence (see [#150](https://github.com/skytable/skytable/issues/150))

## Version 0.5.2 [2021-05-07]

> No breaking changes

- `sky-bench` is less agressive and runs sanity test before benchmarking
- `skyd` now locks the data file (the `data.bin` file)
- The data directory structure has been changed (see #144) (all files are now stored in ./data/\*)
- Fixed 'Connection Forcibly Closed' errors on Windows (see #110)
- Add support for line-editing and keyboard shortcuts on `skysh` (see #142)
- Fixed problems while parsing snapshots in the snapshot directory (see #144)
- The old data directory structure has been deprecated (see #144)
- Official support for 32-bit platforms (see #139)
- Tier-2 Support for Linux musl (x86_64) (see #136, #135)

## Version 0.5.1 [2021-03-17]

> No breaking changes

- Built-in TLS/SSL support
- Custom host/port settings in `sky-bench`
- Mock keys can be created with `sky-bench`
- Security patch for VE/S/00001 [(CVE-2021-32814)](https://nvd.nist.gov/vuln/detail/CVE-2021-32814)
- Escaping for spaces in `skysh`
- `tdb` is now called `skyd` (short for 'Skytable Daemon')

## Version 0.5.0 [2020-11-19]

> This release introduces breaking changes!

- Command line configuration added to `tdb`
- ⚠ Positional arguments in `tsh` and `tdb-bench` have been removed
- `MKSNAP` now has an _enhanced version_ which enables snapshots to be created even if they're disabled on the server side
- If `BGSAVE` fails, no more writes will be accepted on the server side. All commands that try to modify data will return an internal server error
- `tdb-bench` now provides JSON output with the `--json` flag
- The `Dockerfile` was fixed to use command line arguments instead of the configuration file which caused problems
- The `enabled` key under the `snapshots` key in the configuration file has been removed

### Upgrading

- Users who ran `tsh` like `tsh 172.17.0.1 2003` will now need to run:

```shell
tsh -h 172.17.0.1 -p 2003
```

- Users who ran `tdb-bench` like `tdb-bench 10 100000 4` will now need to run:

```shell
tdb-bench -c 10 -q 100000 -s 4
```

- To enable snapshots, you just have to add the key: there is no need for the `enabled` key. To disable snapshots, you just have to omit the `snapshot` key (block) from your configuration file

## Version 0.4.5 [2020-10-29]

> No breaking changes

This release adds support for automated snapshots, while also adding the `MKSNAP` action for doing the same remotely.

## Version 0.4.4 [2020-10-03]

> No breaking changes

This release adds the following actions: `KEYLEN` and `USET`

## Version 0.4.3 [2020-09-25]

> No breaking changes

This release adds the following actions:
`SSET` , `SUPDATE` , `SDEL` , `DBSIZE` and `FLUSHDB`

## Version 0.4.2 [2020-09-19]

> No breaking changes

This release adds `BGSAVE` for automated background saving (see [#11](https://github.com/skytable/skytable/issues/21))

## Version 0.4.1 [2020-09-06]

> No breaking changes

This release adds support for configuration files

## Version 0.4.0 [2020-08-30]

> This release introduces breaking changes

Changes:

- Actions added: `MSET` , `MGET` , `MUPDATE`
- Terrapipe 1.0
- Improved terminal output

Fixes:

- Explicit handling for incomplete responses in `tsh`

### Migrating existing clients

The Terrapipe protocol was revised and promoted to 1.0. This will cause all existing client implementations to break, since the protocol has changed fundamentally. The clients have to implement the [latest spec](https://terrabasedb.github.io/docs/Protocols/terrapipe).

## Version 0.3.2 [2020-08-07]

> No breaking changes

The `tsh` component printed the wrong version number. This has been fixed.

## Version 0.3.1 [2020-08-05]

> This release introduces breaking changes

This release fixes #7, #8. It also adds several under-the-hood optimizations greatly improving query performance.

### Migrating existing clients

The only significant change in the protocol is the new metalayout format: `#a#b#c` instead of the previously proposed `a#b#c#` .

### Disk storage format

The disk storage format was changed rendering existing binary data files incompatible. However, if you have any existing data - which is important, open an issue - because we'll be able to provide a tool that can help you easily migrate your existing datasets - with a one line command - so - no worries!

## Version 0.3.0 [2020-07-28] (⚠ EOL)

> No breaking changes.

This version enables persistence for stored data

## Version 0.2.0 [2020-07-27] (⚠ EOL)

> This release introduces breaking changes

This release implements the latest version of the Terrapipe protocol.

### Migrating existing clients

All clients have to reimplement the Terrapipe protocol to match the [latest spec](https://terrabasedb.github.io/docs/Protocols/unsupported-tp).

## Version 0.1.0 [2020-07-17] (⚠ EOL)

This release provides an experimental client and server implementation.