TDengine supports multiple ways to write data, including SQL, Prometheus, Telegraf, collectd, StatsD, EMQ MQTT Broker, HiveMQ Broker, CSV file, etc. Kafka, OPC and other interfaces will be provided in the future. Data can be inserted in one single record or in batches, data from one or multiple data collection points can be inserted at the same time. TDengine supports multi-thread insertion, out-of-order data insertion, and also historical data insertion.
## <a class="anchor" id="sql"></a> Data Writing via SQL
## <a class="anchor" id="sql"></a> Data Writing via SQL
Applications insert data by executing SQL insert statements through C/C++, Java, Go, C#, Python, Node.js Connectors, and users can manually enter SQL insert statements to insert data through TAOS Shell. For example, the following insert writes a record to table d1001:
...
...
@@ -119,16 +119,16 @@ The format of generated data by Prometheus is as follows:
```json
{
Timestamp:1576466279341,
Value:37.000000,
Value:37.000000,
apiserver_request_latencies_bucket{
component="apiserver",
instance="192.168.99.116:8443",
job="kubernetes-apiservers",
le="125000",
component="apiserver",
instance="192.168.99.116:8443",
job="kubernetes-apiservers",
le="125000",
resource="persistentvolumes",s
cope="cluster",
verb="LIST",
version=“v1"
verb="LIST",
version=“v1"
}
}
```
...
...
@@ -167,13 +167,13 @@ Now you can query the metrics data of Telegraf from TDengine.
Please find taosAdapter configuration and usage from `taosadapter --help` output.
* Modify the configuration file /etc/icinga2/features-enabled/opentsdb.conf
```
object OpenTsdbWriter "opentsdb" {
host = "host to taosAdapter"
port = 6048
}
```
Please find taosAdapter configuration and usage from `taosadapter --help` output.
## <a class="anchor" id="tcollector"></a> Data Writting via TCollector and taosAdapter
TCollector is a client-side process that gathers data from local collectors and pushes the data to OpenTSDB. You run it on all your hosts, and it does the work of sending each host’s data to the TSD (OpenTSDB backend process).
@@ -1335,3 +1335,24 @@ Is not null supports all types of columns. Non-null expression is < > "" and onl
select jtag->'key' from (select jtag from stable) where jtag->'key'>0
```
## Escape character description
- Special Character Escape Sequences
| Escape Sequence | **Character Represented by Sequence** |
| :--------: | ------------------- |
| `\'` | A single quote (') character |
| `\"` | A double quote (") character |
| \n | A newline (linefeed) character |
| \r | A carriage return character |
| \t | A tab character |
| `\\` | A backslash (\) character |
| `\%` | A % character; see note following the table |
| `\_` | A _ character; see note following the table |
- Escape character usage rules
- The escape characters that in a identifier (database name, table name, column name)
1. Normal identifier： The wrong identifier is prompted directly, because the identifier must be numbers, letters and underscores, and cannot start with a number.
2. Backquote`` identifier： Keep it as it is.
- The escape characters that in a data
3. The escape character defined above will be escaped (% and _ see the description below). If there is no matching escape character, the escape character will be ignored.
4. The `\%` and `\_` sequences are used to search for literal instances of % and _ in pattern-matching contexts where they would otherwise be interpreted as wildcard characters.If you use `\%` or `\_` outside of pattern-matching contexts, they evaluate to the strings `\%` and `\_`, not to % and _.
sql="select last(*) from ( select sum(i1) from st where ts>='2017-07-14 11:40:00' and ts<'2017-07-14 12:40:00' interval(10m) order by ts desc );"# desc
tdSql.waitedQuery(sql,1,WAITS)
tdSql.checkData(0,1,192419100)
# add parent query order by
# first
sql="select first(*) from (select first(i1) from st interval(10m) order by ts asc) order by ts desc;"
tdSql.waitedQuery(sql,1,WAITS)
tdSql.checkData(0,1,0)
sql="select first(*) from (select first(i1) from st interval(10m) order by ts desc) order by ts asc;"
tdSql.waitedQuery(sql,1,WAITS)
tdSql.checkData(0,1,0)
# last
sql="select last(*) from (select first(i1) from st interval(10m) order by ts asc) order by ts desc;"
tdSql.waitedQuery(sql,1,WAITS)
tdSql.checkData(0,1,229400)
sql="select last(*) from (select first(i1) from st interval(10m) order by ts desc) order by ts asc;"
sql='select * from stable_1 where t_smallint between 0 and 32767 and t_float between 0 and 3.4E38 and t_nchar is not null and q_smallint between 0 and 32767 and q_nchar is not null and t_binary is not null and q_tinyint is not null and ts < now +1s order by ts ;;;'
