I get the same results without using substr(). Why is this taking so long? I know 100 million rows is a lot, but with sorted indices, shouldn't joining happen in linear time? Adding the indices took several minutes, not hours, and that should be O(n log n) since it has to sort. On s.datadate=d.DATE and substr(s.cusip,1,8)=d.CUSIP Here is the query: Select d.PRC, s.prccd, abs(abs(d.PRC)-s.prccd), * I also tried selecting the top 10k rows and it took 11 hours to complete and another 11 hours to get the row count, but reported that the query finished in 4 minutes. The entire time, task manager shows around 25% CPU usage and 7-8 MB/s disk usage for the process. Then, it takes another several hours for SQLite Studio to count the rows for my results and if I try to open another query window, it becomes unresponsive for these hours. Comment ça marche Rechercher des offres demploi. After migrating from SQLite, it is possible that columns do not have exactly the data type they should have or that indexes are missing. Linscription et faire des offres sont gratuits. Selecting the first 1000 rows takes several hours, but when it's done, SQLite Studio reports that it only took a minute. Chercher les emplois correspondant à Login page in python with sqlite database ou embaucher sur le plus grand marché de freelance au monde avec plus de 22 millions demplois. I have indices on both columns used in the join. I have two large (~100 million rows) tables I'm trying to join.
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