如何从pyspark中的字符串中提取时间

Question

I have a string that contains time in the following pattern that I want to extract in pyspark

......&eventTime=2017-02-22T01%3a02%3a07.1816943Z&......

This is what I tried but didn't work; df_event.EventParameters is a column which contains the time.

df_localTime = pyspark.sql.functions \
          .regexp_extract(df_event.EventParameters, '.*(\\d{4}-\\d{2}-\\d{2}T\\d{2}%3a\\d{2}%3a\\d{2}\\.\\{3}).*', 1) \
          .alias('localTime')

Answer 1

The thing that prevents it from matching anything is this part \\.\\{3}

It basically says

\. match a literal dot  
\{ match a literal open brace  
3 match a literal three  
} match a literal close brace  

I assume you meant there to be a \\d instead.
\\.\\d{3}

So, the stringed regex is now '.*(\\d{4}-\\d{2}-\\d{2}T\\d{2}%3a\\d{2}%3a\\d{2}\\.\\d{3}).*'

which now matches this ( group 1 is highlighted )

......&eventTime= 2017-02-22T01%3a02%3a07.181 6943Z&......

Formatted (for readability)

 .* 
 (                             # (1 start)
      \d{4} - \d{2} - \d{2} 
      T 
      \d{2} %3a \d{2} %3a \d{2} 
      \. \d{3} 
 )                             # (1 end)
 .*