sp: doc: document time and record functions
@@ -20,3 +20,18 @@ The following is the SQL statement syntax supported by Fluent Bit stream process
<characters> := <letter> | <digit> | _ | <characters> <characters>
<value> := true | false | <integer> | <float> | '<string>'
```
+
+### Time Functions
+
+| name | description | example |
+| ---------------- | ------------------------------------------------- | ------------------- |
+| NOW() | adds system time using format: %Y-%m-%d %H:%M:%S. | 2019-03-09 21:36:05 |
+| UNIX_TIMESTAMP() | add current Unix timestamp | 1552196165 |
+
+### Record Functions
+
+| name | description | example |
+| ------------- | ------------------------------------------------------------ | ----------------- |
+| RECORD_TAG() | append Tag string associated to the record | samples |
+| RECORD_TIME() | append record Timestamp in _double_ format: seconds.nanoseconds | 1552196165.705683 |
+
