### install() usage example

Source: https://docs.machbase.com/neo/jsh/modules/service

Example of installing a service named 'alpha' with executable 'echo' and args ['hello']. The callback prints the error message on failure or the snapshot's config name and status on success.

```javascript
const service = require('service');
const client = new service.Client();

client.install({
    name: 'alpha',
    enable: false,
    executable: 'echo',
    args: ['hello'],
}, (err, snapshot) => {
    if (err) {
        console.println(err.message);
        return;
    }
    console.println(snapshot.config.name, snapshot.status);
});
```

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

### Setup: Install dotnet-sdk, create project, add MQTTnet

Source: https://docs.machbase.com/neo/api-mqtt/examples/mqtt-csharp

Setup steps for creating a C# MQTT client project: install the .NET SDK, create a project directory, create a console project targeting net7.0, and add the MQTTnet package version 4.3.3.952.

```sh
brew install dotnet-sdk
```

```sh
mkdir csharp-mqtt && cd csharp-mqtt
```

```sh
dotnet new console --framework net7.0
```

```sh
dotnet add package MQTTnet --version 4.3.3.952
```

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

### Example machadmin workflows

Source: https://docs.machbase.com/dbms/reference/command-line-tools/machadmin

Example workflows: initialize and start, check and stop, and renew the license.

```bash
# Initialize the database and start the server
machadmin -c
machadmin -u

# Check server status, then stop it
machadmin -e
machadmin -s

# Renew the license
machadmin -s
machadmin -t new_license.dat
machadmin -u
```

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

### Install neo-client

Source: https://docs.machbase.com/dbms/development-tools-integration/go

Use the go get command to install the Machbase Neo client module.

```bash
go get github.com/machbase/neo-client/v2
```

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

### Start Cluster with machclusterctl start

Source: https://docs.machbase.com/dbms/installation-deployment-upgrade/cluster-edition

Starts the installed cluster again. The install command already starts the Coordinator, Deployers, Lookup, Brokers, and Warehouses, so this is only needed when you want to start the cluster after it has been stopped.

```bash
machclusterctl start
```

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

### Install full package on Coordinator and Deployer hosts

Source: https://docs.machbase.com/dbms/installation-deployment-upgrade/cluster-edition

Install the full package on the Coordinator host and on each Deployer host. The Coordinator example creates /home/machbase/coordinator and extracts the tarball there; the Deployer example creates /home/machbase/deployer and extracts the same tarball there. Run each on the host for its corresponding role.

```bash
mkdir -p /home/machbase/coordinator
scp machbase@package-host:/path/to/machbase-cluster-8.7.0.official-LINUX-X86-64-release.tgz /home/machbase/
tar zxf /home/machbase/machbase-cluster-8.7.0.official-LINUX-X86-64-release.tgz -C /home/machbase/coordinator
```

```bash
mkdir -p /home/machbase/deployer
scp machbase@package-host:/path/to/machbase-cluster-8.7.0.official-LINUX-X86-64-release.tgz /home/machbase/
tar zxf /home/machbase/machbase-cluster-8.7.0.official-LINUX-X86-64-release.tgz -C /home/machbase/deployer
```

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

### ALTER SYSTEM INSTALL LICENSE grammar and examples

Source: https://docs.machbase.com/dbms/reference/sql/syntax/system-session-alter-syntax

Grammar and examples for installing a license. The default path is $MACHBASE_HOME/conf/license.dat; a specified path is given as a quoted string after '='.

```sql
-- Default path ($MACHBASE_HOME/conf/license.dat)
alter_system_install_license_stmt ::= 'ALTER SYSTEM INSTALL LICENSE'

-- Specified path
alter_system_install_license_path_stmt ::= 'ALTER SYSTEM INSTALL LICENSE' '=' "'" path "'"
```

```sql
-- Install from the default path
ALTER SYSTEM INSTALL LICENSE;

-- Install from a specified path
ALTER SYSTEM INSTALL LICENSE = '/tmp/new_license.dat';
```

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

### Prepare example LOOKUP and TAG tables

Source: https://docs.machbase.com/dbms/lookup-table-usage/query-analysis

Creates the LOOKUP table ch9_query_master and the TAG table ch9_query_data, then inserts sample rows into both. Use this as the prerequisite setup for the query examples in this section.

```sql
CREATE LOOKUP TABLE ch9_query_master (
    sensor_id VARCHAR(32) PRIMARY KEY,
    site      VARCHAR(32),
    unit      VARCHAR(16),
    status    VARCHAR(16)
);

INSERT INTO ch9_query_master VALUES ('TEMP-01', 'SEOUL', 'C', 'ACTIVE');
INSERT INTO ch9_query_master VALUES ('TEMP-02', 'BUSAN', 'C', 'INACTIVE');

CREATE TAG TABLE ch9_query_data (
    name  VARCHAR(32) PRIMARY KEY,
    time  DATETIME BASETIME,
    value DOUBLE SUMMARIZED
);

INSERT INTO ch9_query_data VALUES ('TEMP-01', TO_DATE('2026-01-01 00:00:00'), 23.5);
INSERT INTO ch9_query_data VALUES ('TEMP-02', TO_DATE('2026-01-01 00:00:00'), 19.0);
```

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

### License info response example

Source: https://docs.machbase.com/neo/api-http/ui-api

Example response from GET /web/api/license. Contains license id, type, customer, project, country code, install date, and issue date.

```json
{
    "success": true,
    "reason": "success or error reason",
    "elapse": "elapse time",
    "data": {
        "id": "license id",
        "type": "type",
        "customer": "customer",
        "project": "project",
        "countryCode": "country code",
        "installDate": "installation date",
        "issueDate": "license issue date"
    }
}
```

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

### sqlTimeformat() usage example

Source: https://docs.machbase.com/neo/tql/utilities

Demonstrates the use of sqlTimeformat with a CSV output in the Asia/Seoul timezone.

```js
FAKE( json({
    [ 1701345032123456789, 10],
    [ 1701345043219876543, 11]
}))
MAPVALUE(0, time(value(0)) )
CSV( sqlTimeformat("YYYY-MM-DD HH24:MI:SS.nnnnnn"), tz("Asia/Seoul") )
```

```text
2023-11-30 20:50:32.123456,10
2023-11-30 20:50:43.219876,11
```

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

### Common machclusterctl command examples

Source: https://docs.machbase.com/dbms/reference/command-line-tools/machclusterctl

Examples of common machclusterctl operations: validate, install, apply, start, stop, status, connect, and export. Includes node-specific start/stop with --node and --type options.

```bash
# Validate YAML
machclusterctl validate -f my_cluster.yaml

# Install a new cluster
machclusterctl install -f my_cluster.yaml

# Apply changes to a running cluster
machclusterctl apply -f my_cluster.yaml

# Start the cluster
machclusterctl start

# Stop/start a specific node or node type
machclusterctl stop --node broker-1
machclusterctl start --type warehouse

# Check status
machclusterctl status

# Connect to a Broker and run SQL
machclusterctl connect

# Stop the cluster
machclusterctl stop

# Export the configuration
machclusterctl export -o cluster_config_backup.yaml
```

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

### Prepare EXAMPLE table and data

Source: https://docs.machbase.com/neo/tql/example-time

Run this SQL to create the EXAMPLE tag table and insert sample data used by the time examples.

```sql
CREATE TAG TABLE IF NOT EXISTS EXAMPLE (
    NAME VARCHAR(20) PRIMARY KEY,
    TIME DATETIME BASETIME,
    VALUE DOUBLE SUMMARIZED
);
INSERT INTO EXAMPLE VALUES('TAG0', TO_DATE('2021-08-12 12:00:00 123:456:789'), 10);
INSERT INTO EXAMPLE VALUES('TAG0', TO_DATE('2021-08-13 12:00:00 123:456:789'), 11);
```

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

### strSprintf() formatting example

Source: https://docs.machbase.com/neo/tql/utilities

Formats a string using a format specifier and provides the resulting output.

```js
FAKE( csv(`world,3.141792`) )
MAPVALUE(1, parseFloat(value(1)))
MAPVALUE(2, strSprintf(`hello %s? %1.2f`, value(0), value(1)))
CSV()
```

```csv
world,3.141792,hello world? 3.14
```

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

### Time function usage

Source: https://docs.machbase.com/neo/tql/utilities

Examples of using the time function with current time and epoch timestamps.

```js
SQL(`select to_char(time), value from example where time < ?`, time('now'))
CSV()
```

```js
SQL(`select to_char(time), value from example where time = ?`, time(1628737200123456789))
CSV()
```

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

### strTrimPrefix(str, prefix) : string

Source: https://docs.machbase.com/neo/tql/utilities

Returns str without the provided leading prefix string. If str doesn't start with prefix, str is returned unchanged.

```APIDOC
## strTrimPrefix(str, prefix) : string

### Description
Returns str without the provided leading prefix string. If str doesn't start with prefix, str is returned unchanged.

### Syntax
`strTrimPrefix(str, prefix) : string`

### Parameters
- **str** (string) - Required - The string to trim.
- **prefix** (string) - Required - The prefix to remove.

### Returns
- **string** - The resulting string.
```

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

### timeAdd('now') usage

Source: https://docs.machbase.com/neo/tql/utilities

Example of using timeAdd with 'now' to query data from 10 seconds ago.

```js
SQL(`select to_char(time), value from example where time < ?`, timeAdd('now', '-10s'))
CSV()
```

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

### ansiTimeformat() usage example

Source: https://docs.machbase.com/neo/tql/utilities

Demonstrates the use of ansiTimeformat with a CSV output in the UTC timezone.

```js
FAKE( json({
    [ 1701345032123456789, 10],
    [ 1701345043219876543, 11]
}))
MAPVALUE(0, time(value(0)) )
CSV( ansiTimeformat("yyyy-mm-dd hh:nn:ss.ffffff"), tz("UTC"))
```

```text
2023-11-30 11:50:32.123456,10
2023-11-30 11:50:43.219876,11
```

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

### timeAdd(epoch) usage

Source: https://docs.machbase.com/neo/tql/utilities

Example of using timeAdd with a specific epoch timestamp to query data from 5 seconds before that time.

```js
SQL(`select to_char(time), value from example where time = ?`, timeAdd(1628737200123456789, '-5s'))
CSV()
```

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

### Math functions with MAPVALUE and CHART

Source: https://docs.machbase.com/neo/tql/utilities

TQL example using math functions (sin, pow) with MAPVALUE to compute a value and render a 3D line chart. The code uses FAKE to generate a meshgrid, MAPVALUE to compute sin(pow(x,2)+pow(y,2))/(pow(x,2)+pow(y,2)), then builds a list and pops values, and finally uses CHART with a line3D series.

```js
FAKE(meshgrid(linspace(-4,4,100), linspace(-4,4, 100)))
MAPVALUE(2,
    sin(pow(value(0), 2) + pow(value(1), 2)) / (pow(value(0), 2) + pow(value(1), 2))
)
MAPVALUE(0, list(value(0), value(1), value(2)))
POPVALUE(1, 2)
CHART(
    plugins("gl"),
    size("600px", "600px"),
    chartOption({
        grid3D:{},
        xAxis3D:{},
        yAxis3D:{},
        zAxis3D:{},
        series:[
            {type: "line3D", data: column(0)},
        ]
    })
)
```

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

### Typical pkg workflow: init, install, run

Source: https://docs.machbase.com/neo/jsh/packages

Shows the typical workflow for creating a project, installing dependencies, and running a script. The commands are executed in the /work directory and assume the pkg CLI is available.

```sh
/work > pkg init demo-app
/work > pkg install github.com/acme/demo
/work > pkg install generic-pkg
/work > pkg run start
```

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

### hrtime() Usage Example

Source: https://docs.machbase.com/neo/jsh/modules/process

Usage example for hrtime(). Creates a start time, then computes the difference from that start, and prints whether the result is an array and its length.

```javascript
const process = require('process');
const start = process.hrtime();
const diff = process.hrtime([start[0], start[1]]);
console.println(Array.isArray(diff), diff.length);
```

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

### simplex() noise with MAPVALUE and CHART

Source: https://docs.machbase.com/neo/tql/utilities

TQL example using simplex() to generate Simplex noise based on seed and dimension values. The code creates a meshgrid, maps the absolute value of simplex(123, x, y) multiplied by 10, and renders a 3D bar chart with a visualMap color range.

```js
FAKE(
    meshgrid(
        linspace(0, 10, 100), linspace(0, 10, 100)
    )
)
MAPVALUE(2, abs( simplex(123, value(0), value(1)) ) * 10)
MAPVALUE(0, list(value(0), value(1), value(2)))
CHART(
    plugins("gl"),
    size("600px", "600px"),
    chartOption({
        visualMap: {
            max: 8,
            inRange:{ color:[ 
                    "#313695", "#74add1", "#e0f3f8",
                    "#fee090",  "#f46d43", "#a50026"]}
        },
        grid3D:{ boxWidth:100, boxDepth:100, boxHeight:20},
        xAxis3D:{}, yAxis3D:{}, zAxis3D:{},
        series:[
            {type: "bar3D", data: column(0), itemStyle:{opacity:1.0}},
        ]
    })
)
```

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

### strTime with sqlTimeformat()

Source: https://docs.machbase.com/neo/tql/utilities

Formats the current time using the sqlTimeformat pattern 'YYYY/MM/DD HH24:MI:SS.nnn' with UTC time zone. The example uses FAKE, MAPVALUE, and MARKDOWN functions to generate and display the result.

```js
FAKE( linspace(0, 1, 1))
MAPVALUE(0, strTime(time("now"), sqlTimeformat("YYYY/MM/DD HH24:MI:SS.nnn"), tz("UTC")), "result")
MARKDOWN(rownum(true))
```

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

### Create Coordinator metadata and start

Source: https://docs.machbase.com/dbms/installation-deployment-upgrade/cluster-edition

Create metadata and start the Coordinator. Run these commands after configuring machbase.conf.

```bash
machcoordinatoradmin -c
machcoordinatoradmin -u
```

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

### Start Deployer process

Source: https://docs.machbase.com/dbms/reference/command-line-tools/machdeployeradmin

Starts the Deployer process using the -u/--startup option.

```bash
machdeployeradmin -u
```

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

### Install paho-mqtt

Source: https://docs.machbase.com/neo/api-mqtt/examples/mqtt-python

Installs the paho-mqtt library via pip. Required for all examples on this page.

```bash
pip install paho-mqtt
```

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

### timeformat() usage

Source: https://docs.machbase.com/neo/tql/utilities

Example of formatting time values in a CSV output using timeformat and a specific timezone.

```js
FAKE( json({
    [ 1701345032123456789, 10],
    [ 1701345043219876543, 11]
}))
MAPVALUE(0, time(value(0)) )
CSV(timeformat("DEFAULT"), tz("Asia/Seoul"))
```

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

### CREATE USER Examples

Source: https://docs.machbase.com/dbms/reference/sql/syntax/user-auth-syntax

Examples of creating a basic user, a user with a specific password policy, and a user with public-key authentication.

```sql
-- Create a basic user
CREATE USER app_user IDENTIFIED BY 'App#1234';

-- Specify password policy
CREATE USER ops_user IDENTIFIED BY 'Ops@Strong1' PASSWORD POLICY HIGH;

-- Create with AUTH KEY (public-key authentication)
CREATE USER app_user IDENTIFIED BY 'App#1234'
WITH AUTH KEY (
    key='-----BEGIN PUBLIC KEY-----\nMFkw...(omitted)...==\n-----END PUBLIC KEY-----\n',
    valid_before='2047-12-31',
    comment='initial key'
);
```

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

### strTime with numeric timeformat

Source: https://docs.machbase.com/neo/tql/utilities

Formats the current time using a numeric time format pattern '2006/01/02 15:04:05.999' with UTC time zone. The example uses FAKE, MAPVALUE, and MARKDOWN functions to generate and display the result.

```js
FAKE( linspace(0, 1, 1))
MAPVALUE(0, strTime(time("now"), "2006/01/02 15:04:05.999", tz("UTC")), "result")
MARKDOWN(rownum(true))
```

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

### strTime with named timeformat

Source: https://docs.machbase.com/neo/tql/utilities

Formats the current time using the named time format 'RFC822' with UTC time zone. The example uses FAKE, MAPVALUE, and MARKDOWN functions to generate and display the result.

```js
FAKE( linspace(0, 1, 1))
MAPVALUE(0, strTime(time("now"), "RFC822", tz("UTC")), "time")
MARKDOWN(rownum(true))
```

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

### Rollup Thread Lifecycle Examples

Source: https://docs.machbase.com/neo/sql/rollup

Practical examples of starting, stopping, and forcing rollup aggregation.

```sql
EXEC ROLLUP_START('_tag_data_rollup_30sec');
EXEC ROLLUP_STOP('_tag_data_rollup_10min');
EXEC ROLLUP_FORCE('_tag_rollup_hour'); -- Process pending data for the hourly rollup now
```

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

### MQTT client usage example

Source: https://docs.machbase.com/neo/jsh/modules/mqtt

A complete example demonstrating client initialization, event handling for connection, subscription, messaging, and disconnection.

```js
const mqtt = require('mqtt');

const client = new mqtt.Client({
    servers: ['tcp://127.0.0.1:1883'],
    username: 'user',
    password: 'pass',
    keepAlive: 60,
    connectRetryDelay: 2000,
    connectTimeout: 10 * 1000,
    cleanStartOnInitialConnection: true,
});

client.on('open', () => {
    console.println('Connected');
    client.subscribe('test/topic', {
        qos: 0,
        properties: {
            subscriptionIdentifier: 7,
        },
    });
});

client.on('subscribed', (topic, reason) => {
    console.println('Subscribed:', topic, 'reason:', reason);
    client.publish('test/topic', 'Hello, MQTT!');
});

client.on('message', (msg) => {
    console.println('Message:', msg.topic, msg.payloadText);
    client.unsubscribe(msg.topic, {
        properties: {
            user: {
                source: 'example',
            },
        },
    });
});

client.on('unsubscribed', (topic, reason) => {
    console.println('Unsubscribed:', topic, 'reason:', reason);
    client.close();
});

client.on('error', (err) => {
    console.println('Error:', err.message);
});

client.on('close', () => {
    console.println('Disconnected');
});
```

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

### networkInterfaces() Usage Example

Source: https://docs.machbase.com/neo/jsh/modules/os

Example usage of networkInterfaces() to get the interface object and print its type.

```javascript
const os = require('os');
const ifaces = os.networkInterfaces();
console.println(typeof ifaces);
```

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

### install() syntax

Source: https://docs.machbase.com/neo/jsh/modules/service

Syntax for client.install(config, callback). Installs a service from a config object and returns the installed service snapshot.

```javascript
client.install(config, callback)
```

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

### parseBool example with code and result

Source: https://docs.machbase.com/neo/tql/utilities

Parses the string 'True' into a boolean value using the parseBool function. The code uses FAKE, MAPVALUE, and JSON functions, and the result shows the parsed value in a JSON response.

```js
FAKE( csv(`world,True`) )
MAPVALUE(1, parseBool(value(1)))
JSON()
```

```json
{
    "data": {
        "columns": [ "column0", "column1" ],
        "types": [ "string", "bool" ],
        "rows": [ [ "world", true ] ]
    },
    "success": true,
    "reason": "success",
    "elapse": "122.667µs"
}
```

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

### parseFloat example with code and result

Source: https://docs.machbase.com/neo/tql/utilities

Parses the string '3.141792' into a float number using the parseFloat function. The code uses FAKE, MAPVALUE, and JSON functions, and the result shows the parsed value in a JSON response.

```js
FAKE( csv(`world,3.141792`) )
MAPVALUE(1, parseFloat(value(1)))
JSON()
```

```json
{
    "data": {
        "columns": [ "column0", "column1" ],
        "types": [ "string", "double" ],
        "rows": [ [ "world", 3.141792 ] ]
    },
    "success": true,
    "reason": "success",
    "elapse": "140.125µs"
}
```

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

### servicectl start/stop usage example

Source: https://docs.machbase.com/neo/jsh/services

Usage example for starting and stopping the service named 'alpha'.

```sh
/work > servicectl start alpha
/work > servicectl stop alpha
```

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

### platform() and arch() usage example

Source: https://docs.machbase.com/neo/jsh/modules/fs

Usage example showing how to print the runtime platform and architecture using console.println.

```javascript
const fs = require('fs');
console.println(fs.platform());
console.println(fs.arch());
```

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

### Start Deployer

Source: https://docs.machbase.com/dbms/installation-deployment-upgrade/cluster-edition

Create metadata and start the Deployer. Run these commands after configuring machbase.conf.

```bash
machdeployeradmin -c
machdeployeradmin -u
```

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

### servicectl details get JSON output example

Source: https://docs.machbase.com/neo/jsh/services

Usage example for `servicectl details get` with `--format json` and a specific key. When a key is given, the output is a JSON object containing only that key.

```sh
/work > servicectl details get alpha labels --format json
{
  "labels": {
    "tier": "gold"
  }
}
```

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

### Client.install(config, callback)

Source: https://docs.machbase.com/neo/jsh/modules/service

Installs a service with the given configuration.

```APIDOC
## Client.install(config, callback)

### Description
Installs a service using the provided configuration.

### Method
RPC

### Endpoint
install(config, callback)

### Parameters
- **config** (Object) - Required - Service configuration object.
- **callback** (Function) - Required - Callback function with signature (err, result).

### Request Example
```js
client.install({ name: 'my-service', ... }, (err, result) => {
    if (err) console.println(err.message);
});
```

### Response
- **result** (Object) - The install result.
```

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

### client.install(config, callback)

Source: https://docs.machbase.com/neo/jsh/modules/service

Installs a service from a config object and returns the installed service snapshot.

```APIDOC
## client.install(config, callback)

### Description
Installs a service from a config object and returns the installed service snapshot.

### Method
install

### Endpoint
client.install(config, callback)

### Parameters
#### Request Body
- **config** (object) - Required - The service configuration object.
  - **name** (string) - Required - The name of the service.
  - **enable** (boolean) - Required - Whether the service is enabled.
  - **executable** (string) - Required - The executable to run.
  - **args** (array) - Optional - Arguments for the executable.

#### Callback
- **callback** (function) - Required - Callback function with (err, snapshot).

### Request Example
```js
client.install({
    name: 'alpha',
    enable: false,
    executable: 'echo',
    args: ['hello'],
}, (err, snapshot) => {
    if (err) {
        console.println(err.message);
        return;
    }
    console.println(snapshot.config.name, snapshot.status);
});
```

### Response
#### Success Response
- **snapshot** (object) - The installed service snapshot.
  - **config** (object) - The service configuration.
  - **status** (string) - The service status.

#### Response Example
```js
{
  "config": {
    "name": "alpha",
    "enable": false,
    "executable": "echo",
    "args": ["hello"]
  },
  "status": "installed"
}
```
```

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

### param() example with curl GET request

Source: https://docs.machbase.com/neo/tql/basic

A complete example of using param() in a TQL script saved as 'example.tql' and invoking it with a curl GET request. The SQL statement uses a placeholder '?' that is filled by param('name').

```js
SQL( `select * from example where name = ?`, param('name'))
CSV()
```

```bash
curl http://127.0.0.1:5654/db/tql/param.tql?name=TAG0
```

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

### parseArgs.formatHelp() example

Source: https://docs.machbase.com/neo/jsh/modules/util/parseargs

Generates help text for a single-command config with usage, options, and positionals. The example includes options with descriptions and defaults, and prints the resulting help string.

```javascript
const parseArgs = require('util/parseArgs');

const help = parseArgs.formatHelp({
    usage: 'Usage: myapp [options] <file>',
    options: {
        userName: { type: 'string', short: 'u', description: 'User name', default: 'guest' },
        enableDebug: { type: 'boolean', short: 'd', description: 'Enable debug mode', default: false }
    },
    positionals: [
        { name: 'file', description: 'Input file to process' }
    ]
});

console.println(help);
```

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

### SUBSTR Usage Examples

Source: https://docs.machbase.com/dbms/reference/sql/functions/functions-full

Examples demonstrating SUBSTR with various start and length parameters on a sample table.

```sql
Mach> CREATE LOG TABLE substr_table (c1 VARCHAR(10));
Created successfully.

Mach> INSERT INTO substr_table values('ABCDEFG');
1 row(s) inserted.

Mach> INSERT INTO substr_table values('abstract');
1 row(s) inserted.

Mach> SELECT SUBSTR(c1, 1, 1) FROM substr_table;
SUBSTR(c1, 1, 1)
--------------------
a
A
[2] row(s) selected.

Mach> SELECT SUBSTR(c1, 3, 3) FROM substr_table;
SUBSTR(c1, 3, 3)
--------------------
str
CDE
[2] row(s) selected.

Mach> SELECT SUBSTR(c1, 2) FROM substr_table;
SUBSTR(c1, 2)
-----------------
bstract
BCDEFG
[2] row(s) selected.

Mach> drop table substr_table;
Dropped successfully.
```

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

### Create and populate example table

Source: https://docs.machbase.com/neo/tql/reading

SQL statements to create a tag table and insert sample data for testing TQL queries.

```sql
CREATE TAG TABLE IF NOT EXISTS EXAMPLE (
    NAME VARCHAR(20) PRIMARY KEY,
    TIME DATETIME BASETIME,
VALUE DOUBLE SUMMARIZED);

INSERT INTO EXAMPLE VALUES('TAG0', TO_DATE('2021-08-12'), 10);
INSERT INTO EXAMPLE VALUES('TAG0', TO_DATE('2021-08-13'), 11);
```

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

### servicectl details get box output example

Source: https://docs.machbase.com/neo/jsh/services

Usage example showing the default box output for `servicectl details get alpha`. The table lists keys, types, and values for the service's runtime details.

```sh
/work > servicectl details get alpha
DETAILS (3)
┌─────────┬─────────┬────────────────────┐
│ KEY     │ TYPE    │ VALUE              │
├─────────┼─────────┼────────────────────┤
│ enabled │ boolean │ true               │
│ labels  │ object  │ {"tier":"gold"}    │
│ retries │ number  │ 3                  │
└─────────┴─────────┴────────────────────┘
```

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

### Drop table via HTTP GET

Source: https://docs.machbase.com/neo/api-http/create-drop

Example of dropping a table using a direct HTTP GET request.

```http
GET http://127.0.0.1:5654/db/query
    ?q=drop table EXAMPLE
```

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

### Run Machbase Go Examples

Source: https://docs.machbase.com/dbms/development-tools-integration/go

Commands to execute the provided example scripts located in the _example/ directory of the neo-client repository.

```bash
go run ./_example/query.go -s 127.0.0.1:5656 -u sys -p manager
go run ./_example/append.go -s 127.0.0.1:5656 -u sys -p manager
go run ./_example/insert.go -s 127.0.0.1:5656 -u sys -p manager
go run ./_example/scanbytag.go -s 127.0.0.1:5656 -u sys -p manager
```

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

### TOP_K usage example

Source: https://docs.machbase.com/dbms/reference/sql/functions/functions-full

Example query using TOP_K to get the top 3 most frequent alarm codes from event_log. Example result shows format '101:532,205:317,301:90'.

```sql
SELECT TOP_K(alarm_code, 3)
FROM event_log;
```

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

### Full MQTT client example in Go

Source: https://docs.machbase.com/neo/api-mqtt/examples/mqtt-go

Complete Go program demonstrating MQTT client usage with machbase-neo: connects, subscribes to replies, checks table existence, creates a tag table, inserts data, appends 100 records, queries, and disconnects. Includes comments on topic vs payload table specification.

```go
package main

import (
	"fmt"
	"sync"
	"time"

	paho "github.com/eclipse/paho.mqtt.golang"
)

func main() {
	wg := sync.WaitGroup{}

	// paho mqtt client options
	opts := paho.NewClientOptions()
	opts.SetCleanSession(true)
	opts.SetConnectRetry(false)
	opts.SetAutoReconnect(false)
	opts.SetProtocolVersion(4)
	opts.SetClientID("machbase-mqtt-cli")
	opts.AddBroker("127.0.0.1:5653")
	opts.SetKeepAlive(30 * time.Second)

	// connect to server with paho mqtt client
	client := paho.NewClient(opts)
	connectToken := client.Connect()
	connectToken.WaitTimeout(1 * time.Second)
	if connectToken.Error() != nil {
		panic(connectToken.Error())
	}

	client.Subscribe("db/reply/#", 1, func(_ paho.Client, msg paho.Message) {
		defer wg.Done()

		buff := msg.Payload()
		str := string(buff)
		fmt.Println("RECV", msg.Topic(), " :", str)
	})

	// check table existence
	jsonStr := `{ "q": "select count(*) from M$SYS_TABLES where name = 'TAGDATA'" }`
	wg.Add(1)
	client.Publish("db/query", 1, false, []byte(jsonStr))
	wg.Wait()

	// create table
	jsonStr = `{
			"q": "create tag table if not exists TAGDATA (name varchar(200) primary key, time datetime basetime, value double summarized, jstr varchar(80))"
		}`
	wg.Add(1)
	client.Publish("db/query", 1, false, []byte(jsonStr))
	wg.Wait()

	// insert
	jsonStr = `{
			"reply": "db/reply",
			"data": {
				"columns":["name", "time", "value"],
				"rows": [
					[ "my-car", 1670380342000000000, 32.1 ],
					[ "my-car", 1670380343000000000, 65.4 ],
					[ "my-car", 1670380344000000000, 76.5 ]
				]
			}
		}`
	// it is also possible to specify table in the topic like `db/write/TAGDATA`,
	// if both (topic and payload) ways used in a time, table name of payload will be taken by server
	wg.Add(1)
	client.Publish("db/write/TAGDATA", 1, false, []byte(jsonStr))
	wg.Wait()

	// append
	for i := 0; i < 100; i++ {
		// both forms are available
		// 1) append a single record: `[ columns... ]`
		// 2) append multiple records: `[ [columns...], [columns...] ]`
		jsonStr = fmt.Sprintf(`[ "my-car", %d, %.1f, "{\"speed\":\"%.1fkmh\",\"lat\":37.38906,\"lon\":127.12182}" ]`,
			time.Now().UnixNano(),
			float32(80+i),
			float32(80+i))
		client.Publish("db/append/TAGDATA", 1, false, []byte(jsonStr))
	}

	// select
	jsonStr = `{ "q":"select count(*) from TAGDATA" }`
	wg.Add(1)
	client.Publish("db/query", 1, false, []byte(jsonStr))
	wg.Wait()

	client.Unsubscribe("db/reply/#")
	// disconnect mqtt connection
	client.Disconnect(100)
}
```

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

### CREATE TABLE examples

Source: https://docs.machbase.com/dbms/reference/sql/syntax/ddl-syntax

Examples of creating LOG, TAG, LOOKUP, VOLATILE, and TRANSACTION tables, including metadata, properties, IF NOT EXISTS, and NOT NULL constraints.

```sql
-- Create a LOG table with the explicit LOG keyword.
CREATE LOG TABLE sensor_log (
    id      INTEGER,
    name    VARCHAR(64),
    value   DOUBLE,
    status  VARCHAR(20)
);

-- Create a TAG table: BASETIME required; SUMMARIZED marks the ROLLUP column.
CREATE TAG TABLE tag (
    name  VARCHAR(40) PRIMARY KEY,
    time  DATETIME BASETIME,
    value DOUBLE SUMMARIZED
);

-- TAG table with metadata and properties
CREATE TAG TABLE sensors (
    name     VARCHAR(40) PRIMARY KEY,
    time     DATETIME BASETIME,
    value    DOUBLE SUMMARIZED
) METADATA (
    location VARCHAR(100),
    unit     VARCHAR(20)
) TAG_PARTITION_COUNT = 4;

-- LOOKUP table (PRIMARY KEY required)
CREATE LOOKUP TABLE devices (
    device_id  VARCHAR(40) PRIMARY KEY,
    ip         IPV4,
    status     VARCHAR(20)
);

-- VOLATILE table
CREATE VOLATILE TABLE cache_data (
    id    INTEGER PRIMARY KEY,
    value DOUBLE
);

-- Exact fixed-point columns in a TRANSACTION table
CREATE TRANSACTION TABLE invoice (
    id      LONG PRIMARY KEY,
    amount  DECIMAL(18,2),
    tax     NUMERIC(18,4)
);

-- Use IF NOT EXISTS
CREATE TAG TABLE IF NOT EXISTS tag (
    name  VARCHAR(40) PRIMARY KEY,
    time  DATETIME BASETIME,
    value DOUBLE SUMMARIZED
);

-- NOT NULL constraint
CREATE TABLE t1 (
    c1 INTEGER NOT NULL,
    c2 VARCHAR(200)
);
```

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

### GET /web/api/pkgs/insall/:name

Source: https://docs.machbase.com/neo/api-http/ui-api

Installs a package by name.

```APIDOC
## GET /web/api/pkgs/insall/:name

### Description
Install package

### Method
GET

### Endpoint
/web/api/pkgs/insall/:name

### Parameters
#### Path Parameters
- **name** (string) - Required - Install package name

### Response
#### Success Response (200)
- **success** (boolean) - Success flag
- **reason** (string) - Reason
- **data** (object) - Optional, omitted if empty
- **log** (string) - Log message
- **elapse** (string) - Elapsed time

#### Response Example
{
    "success": true,
    "reason": "success",
    "data":{}, // omitempty
    "log":"",
    "elapse": "23.1491ms"
}
```

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

### servicectl controller usage examples

Source: https://docs.machbase.com/neo/jsh/commands

Usage examples for servicectl controller. Shows metrics, resets counters, and gets metrics (alias).

```sh
servicectl controller metrics
servicectl controller reset
servicectl controller get
```

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

### start() syntax

Source: https://docs.machbase.com/neo/jsh/modules/service

Syntax for client.start(name, callback). Starts a service and returns the updated service snapshot.

```javascript
client.start(name, callback)
```

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

### CLI example for toTUILines()

Source: https://docs.machbase.com/neo/jsh/modules/vizspec

CLI example for toTUILines(). Invokes the 'viz lines' command with height 5, series series-1, and input file sample.json.

```sh
viz lines --height 5 --series series-1 sample.json
```

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

### Create LOG table, add indexes, and compare EXPLAIN plans

Source: https://docs.machbase.com/dbms/log-table-usage/index-performance

Creates a LOG table with sample rows, adds LSM, KEYWORD, and BITMAP indexes, flushes table and index, then runs EXPLAIN and SEARCH queries plus SHOW INDEXES to compare access paths before and after index creation. The search returns rows 2 and 3; these rows illustrate behavior, not performance.

```sql
CREATE LOG TABLE ch7_index (
    event_id   INTEGER,
    event_time DATETIME,
    severity   SHORT,
    message    VARCHAR(256)
);
INSERT INTO ch7_index VALUES (
    1, TO_DATE('2026-01-01 10:00:00', 'YYYY-MM-DD HH24:MI:SS'), 1, 'service started');
INSERT INTO ch7_index VALUES (
    2, TO_DATE('2026-01-01 10:01:00', 'YYYY-MM-DD HH24:MI:SS'), 3, 'database timeout');
INSERT INTO ch7_index VALUES (
    3, TO_DATE('2026-01-01 10:02:00', 'YYYY-MM-DD HH24:MI:SS'), 3, 'connection timeout');

EXPLAIN SELECT event_id FROM ch7_index WHERE severity = 3;

CREATE INDEX ch7_index_time ON ch7_index(event_time) INDEX_TYPE LSM;
CREATE INDEX ch7_index_message ON ch7_index(message) INDEX_TYPE KEYWORD;
CREATE INDEX ch7_index_severity ON ch7_index(severity)
    INDEX_TYPE BITMAP BITMAP_ENCODE = RANGE;

EXEC TABLE_FLUSH(ch7_index);
EXEC INDEX_FLUSH(ch7_index);

EXPLAIN SELECT event_id FROM ch7_index WHERE severity = 3;
EXPLAIN SELECT event_id FROM ch7_index WHERE message SEARCH 'timeout';

SELECT event_id FROM ch7_index
 WHERE message SEARCH 'timeout'
 ORDER BY event_id;
SHOW INDEXES;
```

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

### Install from JSON file: servicectl install <config.json>

Source: https://docs.machbase.com/neo/jsh/services

Syntax and usage example for installing a service from a JSON file. The file name is determined by the service 'name' field; if it contains "name": "alpha", the installed configuration is stored as /etc/services/alpha.json.

```sh
servicectl install <config.json>
```

```sh
/work > servicectl install svc.json
```

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

### Complete Go example with machgo package

Source: https://docs.machbase.com/neo/tutorials/cli-go

Complete Go example using the machgo package to connect to a Machbase database, create a tag table, insert sample data, and query it. Demonstrates the recommended workflow for Go developers, including configuration, connection with password, and error handling.

```go
package main

import (
    "context"
    "fmt"
    "log"
    "time"

    "github.com/machbase/neo-server/v8/api"
    "github.com/machbase/neo-server/v8/api/machgo"
)

func main() {
    // Configure database connection
    conf := &machgo.Config{
        Host: "127.0.0.1",
        Port: 5656,
        MaxOpenConn: 10,
        MaxOpenQuery: 5,
    }
    
    db, err := machgo.NewDatabase(conf)
    if err != nil {
        panic(err)
    }
    ctx := context.Background()
    
    // Connect to database
    conn, err := db.Connect(ctx, api.WithPassword("sys", "manager"))
    if err != nil {
        log.Fatal(err)
    }
    defer conn.Close()
    
    // Create a sample table
    result := conn.Exec(ctx, `
        CREATE TAG TABLE IF NOT EXISTS sample_data (
            name VARCHAR(100) primary key,
            time DATETIME basetime,
            value DOUBLE
        )
    `)
    if err := result.Err(); err != nil {
        log.Fatal(err)
    }
    
    // Insert sample data
    for i := 0; i < 5; i++ {
        result := conn.Exec(ctx,
            `INSERT INTO sample_data VALUES (?, ?, ?)`,
            fmt.Sprintf("sensor_%d", i), time.Now(), float64(i)*1.5)
        if err := result.Err(); err != nil {
            log.Fatal(err)
        }
    }
    
    // Query the data
    rows, err := conn.Query(ctx, `SELECT name, time, value FROM sample_data ORDER BY time`)
    if err != nil {
        log.Fatal(err)
    }
    defer rows.Close()
    
    fmt.Println("Retrieved data:")
    for rows.Next() {
        var name string
        var tm time.Time
        var value float64
        
        if err := rows.Scan(&name, &tm, &value); err != nil {
            log.Fatal(err)
        }
        tm = tm.Local()
        fmt.Printf("Name: %s, Time: %s, Value: %.2f\n", 
            name, tm.Format(time.RFC3339), value)
    }
}
```