@@ -181,6 +181,14 @@ In TDengine, the first column of all tables must be a timestamp. This column is
select_rowts,max(current)frommeters;
```
**\_IROWTS**
The \_IROWTS pseudocolumn can only be used with INTERP function. This pseudocolumn can be used to retrieve the corresponding timestamp column associated with the interpolation results.
| 3 | _ROWTS pseudocolumn | Added | Indicates the primary key. Alias of _C0.
| 4 | INFORMATION_SCHEMA | Added | Database for system metadata containing all schema definitions
| 5 | PERFORMANCE_SCHEMA | Added | Database for system performance information.
| 6 | Connection queries | Deprecated | Connection queries are no longer supported. The syntax and interfaces are deprecated.
| 7 | Mixed operations | Enhanced | Mixing scalar and vector operations in queries has been enhanced and is supported in all SELECT clauses.
| 8 | Tag operations | Added | Tag columns can be used in queries and clauses like data columns.
| 9 | Timeline clauses and time functions in supertables | Enhanced | When PARTITION BY is not used, data in supertables is merged into a single timeline.
| 4 | _IROWTS pseudocolumn | Added | Used to retrieve timestamps with INTERP function.
| 5 | INFORMATION_SCHEMA | Added | Database for system metadata containing all schema definitions
| 6 | PERFORMANCE_SCHEMA | Added | Database for system performance information.
| 7 | Connection queries | Deprecated | Connection queries are no longer supported. The syntax and interfaces are deprecated.
| 8 | Mixed operations | Enhanced | Mixing scalar and vector operations in queries has been enhanced and is supported in all SELECT clauses.
| 9 | Tag operations | Added | Tag columns can be used in queries and clauses like data columns.
| 10 | Timeline clauses and time functions in supertables | Enhanced | When PARTITION BY is not used, data in supertables is merged into a single timeline.
_taosSql_implementsGo's `database/sql/driver` interface via cgo. You can use the [`database/sql`](https://golang.org/pkg/database/sql/) interface by simply introducing the driver.
For native connection, you need to verify that both the client driver and the Python connector itself are installed correctly. The client driver and Python connector have been installed properly if you can successfully import the `taos` module. In the Python Interactive Shell, you can type.
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@@ -118,7 +118,7 @@ Requirement already satisfied: taospy in c:\users\username\appdata\local\program
Before establishing a connection with the connector, we recommend testing the connectivity of the local TDengine CLI to the TDengine cluster.
Ensure that the TDengine instance is up and that the FQDN of the machines in the cluster (the FQDN defaults to hostname if you are starting a standalone version) can be resolved locally, by testing with the `ping` command.
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@@ -173,7 +173,7 @@ If the test is successful, it will output the server version information, e.g.
The following example code assumes that TDengine is installed locally and that the default configuration is used for both FQDN and serverPort.
The TDengine server running in the container uses the container's hostname to establish a connection. Using TDengine CLI or various connectors (such as JDBC-JNI) to access the TDengine inside the container from outside the container is more complicated. So the above is the simplest way to access the TDengine service in the container and is suitable for some simple scenarios. Please refer to the next section if you want to access the TDengine service in the container from outside the container using TDengine CLI or various connectors for complex scenarios.
@@ -15,6 +15,7 @@ To write Telegraf data to TDengine requires the following preparations.
- The TDengine cluster is deployed and functioning properly
- taosAdapter is installed and running properly. Please refer to the [taosAdapter manual](/reference/taosadapter) for details.
- Telegraf has been installed. Please refer to the [official documentation](https://docs.influxdata.com/telegraf/v1.22/install/) for Telegraf installation.
- Telegraf collects the running status measurements of current system. You can enable [input plugins](https://docs.influxdata.com/telegraf/v1.22/plugins/) to insert [other formats](https://docs.influxdata.com/telegraf/v1.24/data_formats/input/) data to Telegraf then forward to TDengine.
## Configuration steps
<Telegraf/>
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@@ -31,26 +32,27 @@ Use TDengine CLI to verify Telegraf correctly writing data to TDengine and read
```
taos> show databases;
name | created_time | ntables | vgroups | replica | quorum | days | keep | cache(MB) | blocks | minrows | maxrows | wallevel | fsync | comp | cachelast | precision | update | status |
- TDengine take influxdb format data and create unique ID for table names by the rule.
The user can configure `smlChildTableName` parameter to generate specified table names if he/she needs. And he/she also need to insert data with specified data format.
For example, Add `smlChildTableName=tname` in the taos.cfg file. Insert data `st,tname=cpu1,t1=4 c1=3 1626006833639000000` then the table name will be cpu1. If there are multiple lines has same tname but different tag_set, the first line's tag_set will be used to automatically creating table and ignore other lines. Please refer to [TDengine Schemaless](/reference/schemaless/#Schemaless-Line-Protocol)
It's a Lua implementation for [TDengine](https://github.com/taosdata/TDengine), an open-sourced big data platform designed and optimized for the Internet of Things (IoT), Connected Cars, Industrial IoT, and IT Infrastructure and Application Monitoring. You may need to install Lua5.3 .
As TDengine is built with lua-enable with default configure, the built-in lua lib conflicts with external lua lib. The following commands require TDengine built with lua-disable.