Suchergebnisse mit Tag „mapreduce“


MapReduce multiple MongoDB collections into one

There are few better ways for taking a SQL server down than SELECT ... JOIN statements. Don't get me wrong - a good JOIN could really fast, but huge JOIN blocks adding 10 or more foreign tables maybe even without using indexes could easily slow down the biggest SQL server. MongoDB has MapReduce to do the job with much less server impact - but more developer brain usage.