@@ -30,25 +30,31 @@ Application programs can execute `INSERT` statement through connectors to insert
The below SQL statement is used to insert one row into table "d1001".
```sql
INSERT INTO d1001 VALUES (1538548685000, 10.3, 219, 0.31);
INSERT INTO d1001 VALUES (ts1, 10.3, 219, 0.31);
```
`ts1` is Unix timestamp, the timestamps which is larger than the difference between current time and KEEP in config is only allowed. For further detial, refer to [TDengine SQL insert timestamp section](/taos-sql/insert).
### Insert Multiple Rows
Multiple rows can be inserted in a single SQL statement. The example below inserts 2 rows into table "d1001".
`ts1` and `ts2` is Unix timestamp, the timestamps which is larger than the difference between current time and KEEP in config is only allowed. For further detial, refer to [TDengine SQL insert timestamp section](/taos-sql/insert).
### Insert into Multiple Tables
Data can be inserted into multiple tables in the same SQL statement. The example below inserts 2 rows into table "d1001" and 1 row into table "d1002".
`ts1`, `ts2` and `ts3` is Unix timestamp, the timestamps which is larger than the difference between current time and KEEP in config is only allowed. For further detial, refer to [TDengine SQL insert timestamp section](/taos-sql/insert).
For more details about `INSERT` please refer to [INSERT](/taos-sql/insert).
The command of changing database configuration parameters is easy to use, but it's hard to determine whether a parameter is proper or not. In this section we will describe how to determine whether cachesize is big enough.
1. How to check cachesize?
You can use `select * from information_schema.ins_databases;` to get the value of cachesize.
2. How to check cacheload?
You can use `show <db_name>.vgroups;` to check the value of cacheload.
3. Determine whether cachesize is big engough
If the value of `cacheload` is very close to the value of `cachesize`, then it's very probably that `cachesize` is too small. If the value of `cacheload` is much smaller than the value of `cachesize`, then `cachesize` is big enough. You can use this simple principle to determine. Depending on how much memory is available in your system, you can choose to double `cachesize` or incrase it by even 5 or more times.
:::note
Other parameters cannot be modified after the database has been created.
- The number of rows in the result set of `INTERP` is determined by the parameter `EVERY(time_unit)`. Starting from timestamp1, one interpolation is performed for every time interval specified `time_unit` parameter. The parameter `time_unit` must be an integer, with no quotes, with a time unit of: a(millisecond)), s(second), m(minute), h(hour), d(day), or w(week). For example, `EVERY(500a)` will interpolate every 500 milliseconds.
- Interpolation is performed based on `FILL` parameter. For more information about FILL clause, see [FILL Clause](../distinguished/#fill-clause).
- `INTERP` can only be used to interpolate in single timeline. So it must be used with `partition by tbname` when it's used on a STable.
- Pseudocolumn `_irowts` can be used along with `INTERP` to return the timestamps associated with interpolation points(support after version 3.0.1.4).
- Pseudocolumn `_isfilled` can be used along with `INTERP` to indicate whether the results are original records or data points generated by interpolation algorithm(support after version 3.0.2.3).
- Pseudocolumn `_irowts` can be used along with `INTERP` to return the timestamps associated with interpolation points(support after version 3.0.2.0).
- Pseudocolumn `_isfilled` can be used along with `INTERP` to indicate whether the results are original records or data points generated by interpolation algorithm(support after version 3.0.3.0).
- After executing the above steps, the command-line will output the result of `nodejsChecker.js` connecting to the TDengine instance and performing a simple insert and query.
</TabItem>
<TabItem value="rest" label="REST connector">
After installing the TDengine client, use the `restChecker.js` program to verify that the current environment supports Node.js access to TDengine.
Verification in details:
- Create an installation test folder such as `~/tdengine-test`. Download the [restChecker.js source code](https://github.com/taosdata/TDengine/tree/3.0/docs/examples/node/restexample/restChecker.js) to your local.
- Execute the following command from the command-line.
```bash
npm init -y
npm install @tdengine/rest
node restChecker.js
```
- After executing the above steps, the command-line will output the result of `restChecker.js` connecting to the TDengine instance and performing a simple insert and query.
@@ -106,7 +106,7 @@ The parameters described in this document by the effect that they have on the sy
| Applicable | Server only |
| Meaning | The switch for monitoring inside server. The main object of monitoring is to collect information about load on physical nodes, including CPU usage, memory usage, disk usage, and network bandwidth. Monitoring information is sent over HTTP to the taosKeeper service specified by `monitorFqdn` and `monitorProt`.
| Value Range | 0: monitoring disabled, 1: monitoring enabled |
| Default | 1 |
| Default | 0 |
### monitorFqdn
...
...
@@ -179,9 +179,10 @@ The parameters described in this document by the effect that they have on the sy
| Attribute | Description |
| -------- | -------------------------------- |
| Applicable | Server only |
| Meaning | count()/hyperloglog() return value or not if the result data is NULL |
| Meaning | count()/hyperloglog() return value or not if the input data is empty or NULL |
| Vlue Range | 0：Return empty line，1：Return 0 |
| Default | 1 |
| Notes | When this parameter is setting to 1, for queries containing GROUP BY, PARTITION BY and INTERVAL clause, and input data in certain groups or windows is empty or NULL, the corresponding groups or windows have no return values |
@@ -24,7 +24,14 @@ You can compile taosKeeper separately and install it. Please refer to the [taosK
taosKeeper needs to be executed on the terminal of the operating system, it supports three configuration methods: [Command-line arguments](#command-line-arguments-in-detail), [environment variable](#environment-variable-in-detail) and [configuration file](#configuration-file-parameters-in-detail). The precedence of those is Command-line, environment variable and configuration file.
**Make sure that the TDengine cluster is running correctly before running taosKeeper. ** Ensure that the monitoring service in TDengine has been started. For more information, see [TDengine Monitoring Configuration](../config/#monitoring).
**Make sure that the TDengine cluster is running correctly before running taosKeeper.** Ensure that the monitoring service in TDengine has been started. At least the values of `monitor` and `monitorFqdn` need to be set in `taos.cfg`.
```shell
monitor 1
monitorFqdn localhost # taoskeeper's FQDN
```
For more information, see [TDengine Monitoring Configuration](../config/#monitoring).
TDengine is a high-efficient, scalable, high-available distributed time-series database, which makes a lot of optimizations on inserting and querying data, which is far more efficient than normal regular databases. So TDengine can meet the high requirements of IOT and other areas on storing and querying a large amount of data.
TDengine is an open-source, cloud-native time-series database optimized for Internet of Things (IoT), Connected Cars, and Industrial IoT. With its built-in caching, stream processing, and data subscription capabilities, TDengine offers a simplified solution for time-series data processing.
To configure TDengine : edit /etc/taos/taos.cfg
To start service : launchctl start com.tdengine.taosd
To start Taos Adapter : launchctl start com.tdengine.taosadapter
To access TDengine : use taos in shell
If you're experiencing problems installing TDengine, check the file /var/log/taos/tdengine_install.log to help troubleshoot the installation.
TDengine is an open-source, cloud-native time-series database optimized for Internet of Things (IoT), Connected Cars, and Industrial IoT. With its built-in caching, stream processing, and data subscription capabilities, TDengine offers a simplified solution for time-series data processing.
Once it's installed, please take the steps below:
1: open a terminal/shell in Mac
2: if connecting to Cloud Service, follow the instructions on your cloud service account and configure the environment variable
3: if connecting to another TDengine Service, you can also view help information via "taos --help"
4: execute command taos
If you're experiencing problems installing TDengine, check the file /var/log/taos/tdengine_install.log to help troubleshoot the installation.
