* 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.
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
...
@@ -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
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 * 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 ;;;'
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 ;;;'
