Hi Hive Gurus, I have a table with a bunch of columns and another table with a list of columns names coming from the first table. What I want to do is to generate a 2-column table that contains column-value pairs from the 1st table but only for columns defined in the second table. In other words, I have the following tables. Table 1:id as string,col1 as string,col2 as string,...colN as string, Table 2:colname as string I'd like to generate a table with the following schema. Table 3:id as string,colname as string,colvalue as string It is relatively straightforward to do this in two steps. We can run a select query on the 2nd table (column names) to get the column list, and generate another Hive query based on this list, but this approach needs to run two separate queries. Are there more efficient ways of achieving the same? Thanks,Sha Liu
