### Install and Initialize Pre-commit Hooks

Source: https://github.com/awslabs/dynein/blob/main/CONTRIBUTING.md

Installs the pre-commit tool (using Homebrew as an example) and initializes pre-commit hooks for automated linting and checks before committing code.

```shell
brew install pre-commit # (or appropriate for your platform: https://pre-commit.com/)
pre-commit install
```

--------------------------------

### DynamoDB Local Setup and Commands with Dynein

Source: https://context7.com/awslabs/dynein/llms.txt

Instructions for setting up and interacting with DynamoDB Local using Dynein. This includes starting DynamoDB Local via Docker or Kubernetes, and then using Dynein commands with the '--region local' flag to manage tables, data, and perform scans.

```bash
# Start DynamoDB Local with Docker
docker run -p 8000:8000 -d amazon/dynamodb-local

# Or with Kubernetes
kubectl apply -f k8s-deploy-dynamodb-local.yml
kubectl port-forward deployment/dynamodb 8000:8000

# Use --region local for all commands
dynein --region local admin create table test --keys id,S
dynein --region local use test
dynein --region local put "item1" --item '{"name": "Test Item"}'
dynein --region local scan
dynein --region local get "item1"

# Configure port if DynamoDB Local runs on different port
dynein --region local --port 8001 list

# All commands work the same with --region local:
dynein --region local query "key1"
dynein --region local upd "item1" --set "count = count + 1"
dynein --region local export --output-file backup.json --format json
```

--------------------------------

### Install Rustfmt and Clippy Components

Source: https://github.com/awslabs/dynein/blob/main/CONTRIBUTING.md

Installs the rustfmt and clippy components for Rust development, which are recommended for maintaining code quality and enforced by GitHub Actions.

```shell
rustup component add rustfmt clippy
```

--------------------------------

### Install dynein CLI using Homebrew

Source: https://github.com/awslabs/dynein/blob/main/README.md

Install the dynein CLI on macOS or Linux systems using the Homebrew package manager. This command simplifies the installation process.

```bash
brew install dynein
```

--------------------------------

### Install dynein CLI on Linux (x86-64)

Source: https://github.com/awslabs/dynein/blob/main/README.md

Download and install the dynein CLI for Linux x86-64 by fetching the binary, extracting it, and moving it to `/usr/local/bin/`. Includes a verification step using the `--help` command.

```bash
curl -O -L https://github.com/awslabs/dynein/releases/latest/download/dynein-linux.tar.gz
tar xzvf dynein-linux.tar.gz
sudo mv dy /usr/local/bin/
dy --help
```

--------------------------------

### Install dynein CLI on macOS

Source: https://github.com/awslabs/dynein/blob/main/README.md

Download and install the dynein CLI for macOS by downloading the binary, extracting it, and moving it to the system's PATH. Includes verification with `--help` command.

```bash
curl -O -L https://github.com/awslabs/dynein/releases/latest/download/dynein-macos.tar.gz
tar xzvf dynein-macos.tar.gz
mv dy /usr/local/bin/
dy --help
```

--------------------------------

### Build dynein CLI from Source using Cargo

Source: https://github.com/awslabs/dynein/blob/main/README.md

Build and install the dynein CLI from its source code using Cargo, Rust's package manager. This method requires Rust to be installed and involves cloning the repository, navigating into it, and running the installation command.

```bash
git clone [[this_git_repository_url]]
cd dynein
cargo install --locked --path .
./target/release/dy --help
```

--------------------------------

### Basic Table Setup and Querying with Dynein

Source: https://github.com/awslabs/dynein/blob/main/docs/query.md

This snippet demonstrates the basic workflow for setting up a table and querying items using the 'dy' CLI. It includes creating a table, selecting it for use, putting sample data, and performing a simple query based on the partition key.

```bash
dy admin create table query-format --keys pk,S sk,S
dy use query-format
dy put 0001 01
dy put 0001 02
dy put 0001 11
dy put 0001 12
dy query 0001
```

--------------------------------

### Install dynein CLI on macOS (ARM 64)

Source: https://github.com/awslabs/dynein/blob/main/README.md

Download and install the dynein CLI for macOS ARM 64-bit systems by downloading the specific binary, extracting it, and moving it to the system's PATH. Verification via `--help` is included.

```bash
curl -O -L https://github.com/awslabs/dynein/releases/latest/download/dynein-macos-arm.tar.gz
tar xzvf dynein-macos-arm.tar.gz
mv dy /usr/local/bin/
dy --help
```

--------------------------------

### Dynein Non-Strict Query Example (Bash)

Source: https://github.com/awslabs/dynein/blob/main/docs/query.md

Demonstrates how to use Dynein's non-strict format for querying, where the input value does not need to strictly align with the table definition's data type. This format allows for more lenient parsing, which may evolve in the future. It shows examples for less-than-or-equal-to and equality comparisons.

```bash
dy query --non-strict 0001 -s '<= 1'
dynein understands the above expression the same as follows:
dy query --strict 0001 -s '<= "1"'

Also, when you want to specify the equal operator, you can specify its value directly.

dy query --non-strict 0001 -s '01'
It is semantically equivalent to the following command:
dy query --strict 0001 -s '= "01"'
```

--------------------------------

### Bootstrap Sample DynamoDB Tables with Dynein

Source: https://github.com/awslabs/dynein/blob/main/README.md

The `dy bootstrap` command creates sample DynamoDB tables with predefined schemas and populates them with sample data. It also provides example commands to interact with the bootstrapped tables. The available sample tables can be listed using `dy bootstrap --list`.

```bash
$ dy bootstrap

Bootstrapping - dynein will creates 4 sample tables defined here:
https://docs.aws.amazon.com/amazondynamodb/latest/developerguide/AppendixSampleTables.html

'ProductCatalog' - simple primary key table
    Id (N)

'Forum' - simple primary key table
    Name (S)

'Thread' - composite primary key table
    ForumName (S)
    Subject (S)

'Reply' - composite primary key table, with GSI named 'PostedBy-Message-Index'
    Id (S)
    ReplyDateTime (S)

...(snip logs)...

Now all tables have sample data. Try following commands to play with dynein. Enjoy!
  $ dy --region us-west-2 ls
  $ dy --region us-west-2 desc --table Thread
  $ dy --region us-west-2 scan --table Thread
  $ dy --region us-west-2 use --table Thread
  $ dy scan

After you 'use' a table like above, dynein assume you're using the same region & table, which info is stored at ~/.dynein/config.yml and ~/.dynein/cache.yml
Let's move on with the 'us-west-2' region you've just 'use'd...
  $ dy scan --table Forum
  $ dy scan -t ProductCatalog
  $ dy get -t ProductCatalog 101
  $ dy query -t Reply "Amazon DynamoDB#DynamoDB Thread 2"
  $ dy query -t Reply "Amazon DynamoDB#DynamoDB Thread 2"  --sort-key "begins_with 2015-10"
```

--------------------------------

### Dynein Format: String Type Examples

Source: https://github.com/awslabs/dynein/blob/main/docs/format.md

Demonstrates string representation in Dynein format using both single and double quotes. Supports UTF-8 encoding and escape sequences when double quotes are used.

```bash
dy put 15 -i '{"date":"2022-02-22T22:22:22Z"}'
```

```bash
dy put 16 -i "{'date':'2022-02-22T22:22:22Z'}"
```

--------------------------------

### Bootstrap DynamoDB tables and load test data

Source: https://github.com/awslabs/dynein/blob/main/tests/cmd/bootstrap.md

This command creates sample DynamoDB tables and populates them with test data. It allows specifying the AWS region, port for local DynamoDB instances, and the target table name. You can also list available samples using the --list option. It requires the 'dynein' CLI to be installed.

```bash
$ dy bootstrap --help
Create sample tables and load test data for bootstrapping

Usage: dy bootstrap [OPTIONS]

Options:
  -l, --list             
  -s, --sample <SAMPLE>  
  -r, --region <REGION>  The region to use (e.g. --region us-east-1). When using DynamodB Local, use `--region local`.
                         You can use --region option in both top-level and subcommand-level.
  -p, --port <PORT>      Specify the port number. This option has an effect only when `--region local` is used.
  -t, --table <TABLE>    Target table of the operation. You can use --table option in both top-level and subcommand-level.
                         You can store table schema locally by executing `$ dy use`, after that you need not to specify --table on every command.
  -h, --help             Print help

$ dy help bootstrap
Create sample tables and load test data for bootstrapping

Usage: dy bootstrap [OPTIONS]

Options:
  -l, --list             
  -s, --sample <SAMPLE>  
  -r, --region <REGION>  The region to use (e.g. --region us-east-1). When using DynamodB Local, use `--region local`.
                         You can use --region option in both top-level and subcommand-level.
  -p, --port <PORT>      Specify the port number. This option has an effect only when `--region local` is used.
  -t, --table <TABLE>    Target table of the operation. You can use --table option in both top-level and subcommand-level.
                         You can store table schema locally by executing `$ dy use`, after that you need not to specify --table on every command.
  -h, --help             Print help

```

--------------------------------

### Import DynamoDB Items with Dynein

Source: https://github.com/awslabs/dynein/blob/main/README.md

Explains how to import data into a DynamoDB table using the `dy import` command. It covers importing from a JSON file and specifies that JSON is the default format. An example command is provided.

```bash
$ dy import --table target_movie --format json --input-file movie.json
```

--------------------------------

### Dynein Format: Boolean Type Example

Source: https://github.com/awslabs/dynein/blob/main/docs/format.md

Illustrates the usage of boolean type attributes in Dynein format, accepting either 'true' or 'false' values.

```bash
dy put 5 -i '{"true-field": true, "false-field": false}'
```

--------------------------------

### Binary Set in Dynein

Source: https://github.com/awslabs/dynein/blob/main/docs/format.md

Provides an example of storing a binary set using Dynein. Binary sets are defined with `<< ... >>` and can include binary literals (like `b"\x00"`) and base64 encoded strings. All elements must be binary.

```bash
dy put 37 -i '{"binary-set": <<b"\x00", b"0x01", b"0x02", b64"Aw=="}>>}'
```

--------------------------------

### Dynein Interactive Shell Mode

Source: https://context7.com/awslabs/dynein/llms.txt

Demonstrates how to enter and use Dynein's interactive shell mode for executing multiple commands without retyping 'dy'. The shell maintains context like the current table and region between commands. Includes examples for using commands, setting context, and exiting the shell.

```bash
# Start shell mode
dynein --shell

# Now execute commands directly:
dynein> use Movie --region us-west-2
dynein> scan --limit 5
dynein> get 1958 "Touch of Evil"
dynein> query 1960
dynein> put 2024 "New Movie" --item '{"rating": 8.5}'
dynein> exit
```

--------------------------------

### Dynein Format: Null Type Example

Source: https://github.com/awslabs/dynein/blob/main/docs/format.md

Demonstrates how to represent a null value in Dynein format using the 'null' keyword. This is used for attributes with unknown or undefined states.

```bash
dy put 1 -i '{"null-field": null}'
```

--------------------------------

### Export DynamoDB Items to CSV

Source: https://github.com/awslabs/dynein/blob/main/README.md

Illustrates exporting DynamoDB items to a CSV file using the `dy export` command. It demonstrates exporting only specified attributes in addition to the primary keys. Includes an example of the CSV output.

```bash
$ dy export --table Reply --output-file out.csv --format csv --attributes PostedBy,Message
$ cat out.csv
Id,ReplyDateTime,PostedBy,Message
"Amazon DynamoDB#DynamoDB Thread 1","2015-09-15T19:58:22.947Z","User A","DynamoDB Thread 1 Reply 1 text"
...
```

--------------------------------

### Dynein Format: Number Type Examples

Source: https://github.com/awslabs/dynein/blob/main/docs/format.md

Shows how to represent various number types, including integers, fractions, negative numbers, and exponential notation, in Dynein format. Numbers must be decimal and support up to 38 digits of precision.

```bash
dy put 10 -i '{"integer": 1, "fraction": 0.1, "minus": -3, "exponential": -1.23e-3}'
```

--------------------------------

### Batch Write Items with Dynein using --put and --del Options

Source: https://github.com/awslabs/dynein/blob/main/README.md

Demonstrates using the `dy bwrite` command with `--put` and `--del` options to add and remove items individually. This method requires specifying at least a primary key for each item. Examples show combining these options and using them with `--input`.

```bash
$ dy bwrite --put '{"pk": "1", "this_is_set": <<"i","j","k">>}' --put '{"pk": "2", "this_is_set": <<"x","y","z">>}'
$ dy scan
pk  attributes
1   {"this_is_set":["i","j","k"]}
2   {"this_is_set":["x","y","z"]}

$ dy bwrite --del '{"pk": "1"}' --del '{"pk": "2"}' --put '{"pk": "3", "this_is_set": <<"a","b","c">>}'
$ dy scan
pk  attributes
3   {"this_is_set":["a","b","c"]}

$ dy bwrite --del '{"pk": "1"}' --del '{"pk": "2"}' --put '{"pk": "3", "this_is_set": <<"a","b","c">>}' --input request.json
```

--------------------------------

### Create DynamoDB Table using Dynein Admin

Source: https://github.com/awslabs/dynein/blob/main/README.md

The `dy admin create table` command is used to create a new DynamoDB table. This example demonstrates creating a table named `mytable` with a primary key `pk` of type String (S). This command interfaces with the AWS SDK's CreateTable API.

```bash
$ dy admin create table mytable --keys pk,S
```

--------------------------------

### Export DynamoDB Items to JSON and JSONL

Source: https://github.com/awslabs/dynein/blob/main/README.md

Shows how to export items from a DynamoDB table to JSON and JSON Lines (JSONL) formats using the `dy export` command. Covers default JSON export, compact JSON, and the JSONL format for one JSON item per line. It also includes example output.

```bash
$ dy export --table Reply --format json --output-file out.json
$ cat out.json
[
  {
    "PostedBy": "User A",
    "ReplyDateTime": "2015-09-15T19:58:22.947Z",
    "Id": "Amazon DynamoDB#DynamoDB Thread 1",
    "Message": "DynamoDB Thread 1 Reply 1 text"
  },
  {
    "Id": "Amazon DynamoDB#DynamoDB Thread 1",
...
```

```bash
$ dy export --table Reply --format jsonl --output-file out.jsonl
$ cat out.jsonl
{"PostedBy":"User A","ReplyDateTime":"2015-09-15T19:58:22.947Z","Message":"DynamoDB Thread 1 Reply 1 text","Id":"Amazon DynamoDB#DynamoDB Thread 1"}
{"PostedBy":"User B","Message":"DynamoDB Thread 1 Reply 2 text","ReplyDateTime":"2015-09-22T19:58:22.947Z","Id":"Amazon DynamoDB#DynamoDB Thread 1"}
...
```

--------------------------------

### Bootstrap Sample DynamoDB Tables

Source: https://context7.com/awslabs/dynein/llms.txt

Create and populate sample DynamoDB tables with test data. Useful for learning DynamoDB concepts or setting up a test environment quickly. Supports listing available datasets and bootstrapping specific or default sets.

```bash
# List available sample datasets
dy bootstrap --list

# Bootstrap default sample tables (Forum, Thread, Reply, ProductCatalog)
dy bootstrap --region us-west-2

# Bootstrap specific sample dataset
dy bootstrap --sample movie --region us-west-2
```

--------------------------------

### Querying with Sort Key Prefix Condition in Dynein

Source: https://github.com/awslabs/dynein/blob/main/docs/query.md

This example shows how to use the 'dy query' command with a sort key condition to retrieve items whose sort key starts with a specific prefix. It uses the '-s' option with the 'begins_with' operator.

```bash
dy query 0001 -s 'begins_with "0"'
```

--------------------------------

### Display Dynein Help Information

Source: https://github.com/awslabs/dynein/blob/main/README.md

The `dy --help` command displays the main help information for the dynein CLI, including usage instructions, available top-level options, and a list of all available subcommands. It also provides information about configuration file locations and the purpose of the tool.

```bash
$ dy --help
dynein x.x.x
dynein is a command line tool to interact with DynamoDB tables/data using concise interface.
dynein looks for config files under $HOME/.dynein/ directory.

USAGE:
    dy [OPTIONS] <SUBCOMMAND>

FLAGS:
    -h, --help       Prints help information
    -V, --version    Prints version information

OPTIONS:
    -r, --region <region>    The region to use (e.g. --region us-east-1). When using DynamodB Local, use `--region
                             local`. You can use --region option in both top-level and subcommand-level
    -t, --table <table>      Target table of the operation. You can use --table option in both top-level and subcommand-
                             level. You can store table schema locally by executing `$ dy use`, after that
                             you need not to specify --table on every command

SUBCOMMANDS:
    admin        <sub> Admin operations such as creating/updating table or GSI
    backup       Take backup of a DynamoDB table using on-demand backup
    bootstrap    Create sample tables and load test data for bootstrapping
    bwrite       Put or Delete multiple items at one time, up to 25 requests. [API: BatchWriteItem]
    config       <sub> Manage configuration files (config.yml and cache.yml) from command line
    del          Delete an existing item. [API: DeleteItem]
    desc         Show detailed information of a table. [API: DescribeTable]
    export       Export items from a DynamoDB table and save them as CSV/JSON file
    get          Retrieve an item by specifying primary key(s). [API: GetItem]
    help         Prints this message or the help of the given subcommand(s)
    import       Import items into a DynamoDB table from CSV/JSON file
    list         List tables in the region. [API: ListTables]
    put          Create a new item, or replace an existing item. [API: PutItem]
    query        Retrieve items that match conditions. Partition key is required. [API: Query]
    restore      Restore a DynamoDB table from backup data
    scan         Retrieve items in a table without any condition. [API: Scan]
    upd          Update an existing item. [API: UpdateItem]
    use          Switch target table context. After you use the command you don't need to specify table every time,
                 but you may overwrite the target table with --table (-t) option

```

--------------------------------

### Get a Single DynamoDB Item by Primary Key using dy get

Source: https://github.com/awslabs/dynein/blob/main/README.md

Retrieves the full details of a single DynamoDB item using the 'dy get' command. Requires the partition key and sort key for composite primary keys. If the table has a simple primary key, only the partition key is needed. This command is useful for inspecting individual records after scanning or for targeted data retrieval.

```bash
$ dy get 1958 "Touch of Evil"
{
  "info": {
    "actors": [
      "Charlton Heston",
      "Janet Leigh",
      "Orson Welles"
    ],
    "directors": [
      "Orson Welles"
    ],
    "genres": [
      "Crime",
      "Film-Noir",
      "Thriller"
    ],
    "image_url": "http://ia.media-imdb.com/images/M/MV5BNjMwODI0ODg1Nl5BMl5BanBnXkFtZTcwMzgzNjk3OA@@._V1_SX400_.jpg",
    "plot": "A stark, perverse story of murder, kidnapping, and police corruption in a Mexican border town.",
    "rank": 3843,
    "rating": 8.2,
    "release_date": "1958-04-23T00:00:00Z",
    "running_time_secs": 5700
  },
  "title": "Touch of Evil",
  "year": 1958
}
```

--------------------------------

### Manage DynamoDB Table State and Data with Dynein

Source: https://github.com/awslabs/dynein/blob/main/README.md

Shows how to set the current table context using `dy use`, describe the active table's status, put an item into the table, and scan all items in the table. This illustrates basic data manipulation after a table is active and ready.

```bash
$ dy use app_users
$ dy desc
---
name: app_users
region: us-east-1
status: ACTIVE
schema:
  pk: app_id (S)
  sk: user_id (S)
mode: OnDemand
capacity: ~
gsi: ~
lsi: ~
stream: ~
count: 0
size_bytes: 0
created_at: "2020-03-03T13:34:43+00:00"

$ dy put myapp 1234 --item '{"rank": 99}'
Successfully put an item to the table 'app_users'.

$ dy scan
app_id  user_id  attributes
myapp   1234     {"rank":99}
```

--------------------------------

### GET Item with Composite Primary Key

Source: https://github.com/awslabs/dynein/blob/main/README.md

Retrieves a full item from a DynamoDB table using its composite primary key (partition key and sort key). This command is useful when the default scan results are trimmed.

```APIDOC
## GET /item

### Description
Retrieves a single item from a DynamoDB table using its composite primary key.

### Method
GET

### Endpoint
`/item`

### Parameters
#### Path Parameters
- **year** (Number) - Required - The partition key of the item.
- **title** (String) - Required - The sort key of the item.

### Request Example
```bash
$ dy get 1958 "Touch of Evil"
```

### Response
#### Success Response (200)
- **year** (Number) - The partition key of the item.
- **title** (String) - The sort key of the item.
- **info** (Object) - Contains detailed information about the movie, including actors, directors, plot, etc.

#### Response Example
```json
{
  "info": {
    "actors": [
      "Charlton Heston",
      "Janet Leigh",
      "Orson Welles"
    ],
    "directors": [
      "Orson Welles"
    ],
    "genres": [
      "Crime",
      "Film-Noir",
      "Thriller"
    ],
    "image_url": "http://ia.media-imdb.com/images/M/MV5BNjMwODI0ODg1Nl5BMl5BanBnXkFtZTcwMzgzNjk3OA@@._V1_SX400_.jpg",
    "plot": "A stark, perverse story of murder, kidnapping, and police corruption in a Mexican border town.",
    "rank": 3843,
    "rating": 8.2,
    "release_date": "1958-04-23T00:00:00Z",
    "running_time_secs": 5700
  },
  "title": "Touch of Evil",
  "year": 1958
}
```
```

--------------------------------

### Create Global Secondary Index with Dynein

Source: https://github.com/awslabs/dynein/blob/main/README.md

Demonstrates how to add a Global Secondary Index (GSI) to an existing DynamoDB table using the `dy admin create index` command. It shows the command syntax, the resulting table status update, and how to query using the new index.

```bash
$ dy admin create index top_rank_users_index --keys rank,N --table app_users
---
name: app_users
region: us-west-2
status: UPDATING
schema:
  pk: app_id (S)
  sk: user_id (S)
mode: OnDemand
capacity: ~
gsi:
  - name: top_rank_users_index
    schema:
      pk: rank (N)
      sk: ~
    capacity: ~
lsi: ~
stream: ~
count: 0
size_bytes: 0
created_at: "2020-06-02T14:22:56+00:00"

$ dy use app_users
$ dy scan --index top_rank_users_index
```

--------------------------------

### Dynein Format: String Escape Sequences

Source: https://github.com/awslabs/dynein/blob/main/docs/format.md

Provides an example of using escape sequences within double-quoted strings in Dynein format, such as newline and tab characters. Note that escape sequences are not supported with single quotes.

```bash
dy put 17 -i '{"escape":"\"hello\",\tworld!\n"}'
```

--------------------------------

### Create Table

Source: https://context7.com/awslabs/dynein/llms.txt

Creates a new DynamoDB table with specified partition and optional sort keys.

```APIDOC
## Create Table

### Description
Create a new DynamoDB table with specified partition and optional sort keys.

### Method
POST

### Endpoint
/admin/create_table

### Parameters
#### Path Parameters
- **table_name** (string) - Required - The name of the table to create.

#### Query Parameters
- **--keys** (string) - Required - Comma-separated list of keys, each with a type (S=String, N=Number, B=Binary). Format: `partition_key_name,Type [sort_key_name,Type]`
- **--region** (string) - Optional - Specify the AWS region for table creation.

### Request Example
```bash
# Create table with partition key only
dy admin create table my_users --keys user_id,S

# Create table with partition and sort keys
dy admin create table app_users --keys app_id,S user_id,N

# Full example with region
dy admin create table products --keys product_id,N --region us-east-1
```

### Response
#### Success Response (200)
- Returns details of the created table, including name, region, status, schema, and creation timestamp.

#### Response Example
```json
{
  "name": "products",
  "region": "us-east-1",
  "status": "CREATING",
  "schema": {
    "pk": "product_id (N)",
    "sk": "~"
  },
  "mode": "OnDemand",
  "capacity": "~",
  "gsi": "~",
  "created_at": "2024-01-15T10:30:00+00:00"
}
```
```

--------------------------------

### Create DynamoDB Table Imperatively with Dynein

Source: https://github.com/awslabs/dynein/blob/main/README.md

This command demonstrates how to imperatively create a DynamoDB table named 'app_users' using Dynein. It specifies the primary key schema (app_id as partition key, user_id as sort key) and uses On-Demand billing mode. The output shows the initial state of the created table.

```bash
$ dy admin create table app_users --keys app_id,S user_id,S
---
name: app_users
region: us-east-1
status: CREATING
schema:
  pk: app_id (S)
  sk: user_id (S)
mode: OnDemand
capacity: ~
gsi: ~
lsi: ~
stream: ~
count: 0
size_bytes: 0
created_at: "2020-03-03T13:34:43+00:00"
```

--------------------------------

### Calculate Fibonacci Sequence with Dynein

Source: https://github.com/awslabs/dynein/blob/main/README.md

This snippet shows how to calculate Fibonacci numbers using the `dy upd` command to update attributes representing the previous two numbers in the sequence and `dy get` to retrieve the current values. It demonstrates iterative updates to generate the sequence.

```bash
$ dy upd 42 --set "n1 = n2, n2 = n1 + n2"
$ dy get 42 | jq -c '[.n1,.n2]'
[1,1]

$ dy upd 42 --set "n1 = n2, n2 = n1 + n2"
$ dy get 42 | jq -c '[.n1,.n2]'
[1,2]

$ dy upd 42 --set "n1 = n2, n2 = n1 + n2"
$ dy get 42 | jq -c '[.n1,.n2]'
[2,3]

$ dy upd 42 --set "n1 = n2, n2 = n1 + n2"
$ dy get 42 | jq -c '[.n1,.n2]'
[3,5]

$ dy upd 42 --remove "n1,n2"
$ dy get 42
{
  "id": "42"
}
```

--------------------------------

### Create DynamoDB Table (Bash)

Source: https://context7.com/awslabs/dynein/llms.txt

Creates a new DynamoDB table with specified partition and optional sort keys. Supports different data types for keys and allows specifying region and other table configurations. Dependencies: dynein CLI.

```bash
# Create table with partition key only (S=String, N=Number, B=Binary)
dy admin create table my_users --keys user_id,S

# Create table with partition and sort keys
dy admin create table app_users --keys app_id,S user_id,N

# Full example with output:
dy admin create table products --keys product_id,N --region us-east-1

# Output:
# ---
# name: products
# region: us-east-1
# status: CREATING
# schema:
#   pk: product_id (N)
#   sk: ~
# mode: OnDemand
# capacity: ~
# gsi: ~
# created_at: "2024-01-15T10:30:00+00:00"
```

--------------------------------

### List DynamoDB Tables with Dynein

Source: https://github.com/awslabs/dynein/blob/main/README.md

The `dy ls --all-regions` command lists all DynamoDB tables across all available AWS regions. It connects to AWS and retrieves table names, displaying them grouped by region. This command is useful for getting an overview of all your DynamoDB resources.

```bash
$ dy ls --all-regions
DynamoDB tables in region: us-west-2
  EventData
  EventUsers
* Forum
  Thread
DynamoDB tables in region: us-west-1
  No table in this region.
DynamoDB tables in region: us-east-2
  UserBooks
  Users
...
```

--------------------------------

### List DynamoDB Tables (Bash)

Source: https://context7.com/awslabs/dynein/llms.txt

Lists DynamoDB tables in the configured region, all regions, or a specific region. Output is a formatted list of table names. Dependencies: dynein CLI.

```bash
# List tables in configured region
dy list

# List tables in all AWS regions
dy list --all-regions

# List tables in specific region
dy --region us-west-2 list

# Output example:
# DynamoDB tables in region: us-west-2
#   EventData
#   EventUsers
# * Forum
#   Thread
```

--------------------------------

### Describe Table

Source: https://context7.com/awslabs/dynein/llms.txt

Shows detailed information about a DynamoDB table, including schema, indexes, and capacity settings.

```APIDOC
## Describe Table

### Description
Show detailed information about a table including schema, indexes, and capacity settings.

### Method
GET

### Endpoint
/describe_table

### Parameters
#### Path Parameters
- **table_name** (string) - Optional - The name of the table to describe. If not provided, describes the currently selected table.

#### Query Parameters
- **--region** (string) - Optional - Specify the AWS region of the table.
- **--all-tables** (boolean) - Optional - Describe all tables in the specified or configured region.

### Request Example
```bash
# Describe currently selected table
dy desc

# Describe specific table
dy desc Forum --region us-west-2

# Describe all tables in region
dy desc --all-tables
```

### Response
#### Success Response (200)
- Returns detailed information about the table(s), including name, region, status, schema, capacity, indexes, item count, size, and creation timestamp.

#### Response Example
```json
{
  "name": "Forum",
  "region": "us-west-2",
  "status": "ACTIVE",
  "schema": {
    "pk": "Name (S)",
    "sk": "~"
  },
  "mode": "OnDemand",
  "gsi": [
    {
      "name": "CategoryIndex",
      "schema": {
        "pk": "Category (S)"
      }
    }
  ],
  "count": 42,
  "size_bytes": 8192,
  "created_at": "2024-01-01T00:00:00+00:00"
}
```
```

--------------------------------

### Get Item from DynamoDB using Dynein CLI

Source: https://context7.com/awslabs/dynein/llms.txt

Retrieves a single item from a DynamoDB table using its primary key(s). Supports partition key only, or partition and sort keys. Allows specifying consistent read and output formats (JSON, YAML, or raw DynamoDB JSON).

```bash
dy get 101 --table ProductCatalog
dy get 1958 "Touch of Evil" --table Movie
dy get "user123" --consistent-read
dy get 101 --output json
dy get 101 --output yaml
dy get 101 --output raw
```

--------------------------------

### Import with Set Type Inference Disabled (Default)

Source: https://github.com/awslabs/dynein/blob/main/README.md

Demonstrates the default behavior of `dy import` without the `--enable-set-inference` flag. In this mode, JSON lists are always inferred as DynamoDB lists (type 'L'). This example shows importing JSONL data and the resulting DynamoDB item structure.

```bash
$ cat load.json
{"pk":1,"string-set":["1","2","3"]}
{"pk":2,"number-set":[1,2,3]}
{"pk":3,"list":["1",2,"3"]}

$ dy admin create table target_movie -k pk,N
$ dy import --table target_movie --format jsonl --input-file load.json
$ aws dynamodb get-item --table-name target_movie --key '{"pk":{"N":"1"}}'
{
    "Item": {
        "string-set": {
            "L": [
                {
                    "S": "1"
                },
                {
                    "S": "2"
                },
                {
                    "S": "3"
                }
            ]
        },
        "pk": {
            "N": "1"
        }
    }
}
```

--------------------------------

### dy put Command Usage and Options

Source: https://github.com/awslabs/dynein/blob/main/tests/cmd/put.md

This snippet details the command-line usage for 'dy put', including its arguments (Partition Key, Sort Key) and available options. Options allow specifying additional item attributes in JSON format, the AWS region, port for local DynamoDB, and the target table.

```bash
$ dy put --help
Create a new item, or replace an existing item. [API: PutItem]

Usage: dy put [OPTIONS] <PVAL> [SVAL]

Arguments:
  <PVAL>  Partition Key of the target item
  [SVAL]  Sort Key of the target item (if any)

Options:
  -i, --item <ITEM>      Additional attributes put into the item, which should be valid JSON.
                         e.g. --item '{"name": "John", "age": 18, "like": ["Apple", "Banana"]}'
  -r, --region <REGION>  The region to use (e.g. --region us-east-1). When using DynamodB Local, use `--region local`.
                         You can use --region option in both top-level and subcommand-level.
  -p, --port <PORT>      Specify the port number. This option has an effect only when `--region local` is used.
  -t, --table <TABLE>    Target table of the operation. You can use --table option in both top-level and subcommand-level.
                         You can store table schema locally by executing `$ dy use`, after that you need not to specify --table on every command.
  -h, --help             Print help

$ dy help put
Create a new item, or replace an existing item. [API: PutItem]

Usage: dy put [OPTIONS] <PVAL> [SVAL]

Arguments:
  <PVAL>  Partition Key of the target item
  [SVAL]  Sort Key of the target item (if any)

Options:
  -i, --item <ITEM>      Additional attributes put into the item, which should be valid JSON.
                         e.g. --item '{"name": "John", "age": 18, "like": ["Apple", "Banana"]}'
  -r, --region <REGION>  The region to use (e.g. --region us-east-1). When using DynamodB Local, use `--region local`.
                         You can use --region option in both top-level and subcommand-level.
  -p, --port <PORT>      Specify the port number. This option has an effect only when `--region local` is used.
  -t, --table <TABLE>    Target table of the operation. You can use --table option in both top-level and subcommand-level.
                         You can store table schema locally by executing `$ dy use`, after that you need not to specify --table on every command.
  -h, --help             Print help
```

--------------------------------

### Demonstrating Strict Mode Error with Incorrect Type in Dynein

Source: https://github.com/awslabs/dynein/blob/main/docs/query.md

This example shows how Dynein's strict mode handles type mismatches in sort key conditions. Providing a raw number when a string is expected results in an error, highlighting the importance of correct type specification.

```bash
dy query --strict 0001 -s '<= 1'
```

--------------------------------

### Describe DynamoDB Table (Bash)

Source: https://context7.com/awslabs/dynein/llms.txt

Retrieves and displays detailed information about a DynamoDB table, including its schema, indexes, capacity settings, item count, and size. Can describe the currently selected table, a specific table, or all tables in a region. Dependencies: dynein CLI.

```bash
# Describe currently selected table
dy desc

# Describe specific table
dy desc Forum --region us-west-2

# Describe all tables in region
dy desc --all-tables

# Output format:
# ---
# name: Forum
# region: us-west-2
# status: ACTIVE
# schema:
#   pk: Name (S)
#   sk: ~
# mode: OnDemand
# gsi:
#   - name: CategoryIndex
#     schema:
#       pk: Category (S)
# count: 42
# size_bytes: 8192
# created_at: "2024-01-01T00:00:00+00:00"
```

--------------------------------

### Dynein Format: Heredoc Input

Source: https://github.com/awslabs/dynein/blob/main/docs/format.md

Illustrates using a heredoc to input complex Dynein format structures, including both escaped and raw strings, from standard input.

```bash
dy put 19 -i "$(cat <<EOS
{
  "escape":"hello,\tworld!\n",
  "raw":'hello,\tworld!\n'
}
EOS
)"
```

--------------------------------

### Display Dynein Admin Subcommand Help

Source: https://github.com/awslabs/dynein/blob/main/README.md

The `dy admin --help` command displays detailed help for the `admin` subcommand, outlining its purpose for administrative operations on DynamoDB tables and GSIs. It lists the available sub-subcommands like `create`, `delete`, `desc`, and `update`, along with their associated AWS API actions.

```bash
$ dy admin --help
dy-admin x.x.x
<sub> Admin operations such as creating/updating table or GSI

USAGE:
    dy admin [OPTIONS] <SUBCOMMAND>

FLAGS: ...

OPTIONS: ...

SUBCOMMANDS:
    create    Create new DynamoDB table or GSI. [API: CreateTable, UpdateTable]
    delete    Delete a DynamoDB table or GSI. [API: DeleteTable]
    desc      Show detailed information of a table. [API: DescribeTable]
    help      Prints this message or the help of the given subcommand(s)
    list      List tables in the region. [API: ListTables]
    update    Update a DynamoDB table. [API: UpdateTable etc]

```

--------------------------------

### Batch Write Items with Dynein using JSON Input

Source: https://github.com/awslabs/dynein/blob/main/README.md

Illustrates how to use the `dy bwrite --input` command to perform batch put and delete operations by specifying operations in a JSON file that conforms to the BatchWriteItem API Request Syntax.

```bash
$ dy bwrite --input request.json

{
    "__TABLE_NAME__": [
        {
            "PutRequest": {
                "Item": {
                    "pk": { "S": "ichi" },
                    "ISBN": { "S": "111-1111111111" },
                    "Price": { "N": "2" },
                    "Dimensions": { "SS": ["Giraffe", "Hippo" ,"Zebra"] },
                    "PageCount": { "NS": ["42.2", "-19", "7.5", "3.14"] },
                    "InPublication": { "BOOL": false },
                    "Binary": {"B": "dGhpcyB0ZXh0IGlzIGJhc2U2NC1lbmNvZGVk"},
                    "BinarySet": {"BS": ["U3Vubnk=", "UmFpbnk=", "U25vd3k="]},
                    "Nothing": { "NULL": true },
                    "Authors": {
                        "L": [
                            { "S": "Author1" },
                            { "S": "Author2" },
                            { "N": "42" }
                        ]
                    },
                    "Details": {
                        "M": {
                            "Name": { "S": "Joe" },
                            "Age":  { "N": "35" },
                            "Misc": {
                                "M": {
                                    "hope": { "BOOL": true },
                                    "dream": { "L": [ { "N": "35" }, { "NULL": true } ] }
                                }
                            }
                        }
                    }
                }
            }
        }
    ]
}
```