title: Exclude leading NULL values from table
body: <p>To give some context, I am using time series data (one column) and I want to study gaps in the data, represented by NULL values in the data set. Although I expect some leading NULL values that I am not interested in including in my final data set. However the number of leading NULL values will vary between data sets.</p>
  
  <p>I would like to exclude the top x number of rows of my data set where the value of a particular column is NULL, without excluding NULL values that appear lower in the same column. </p>
  
  <p>Any help would be much appreciated.</p>
  
  <p>Thanks!</p>
  
  <p>EDIT: I also know that my first record in the value column is always 1, if that helps.</p>