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Tag: sql

Optimize GROUP_CONCAT in SQL on MySQL

Is there a way to get the following SQL optimized so it would run faster? I encountered the bottleneck are the GROUP_CONCAT’s but I couldn’t find a way by using an alternative or optimizing the query so it would run faster. At the moment the query needs about 3.2s on 2700 entries (mysql database 5…

How to trim leading zero in Hive

How to trim leading zero in Hive, I search too much on google but I didn’t get any correct thing which is useful for my problem. If digit is “00000012300234” want result like “12300234” Answer nothing to do just cast the string in INT it will return 12300234

How to run SQL queries in a loop

How can I run this SQL query multiple times in a loop, where I replace the word ‘pubs’ with another word during each iteration. Is there a way to store an array of strings and loop through them? Answer In general, it’s usually better performance-wise to do bulk or batch queries than queries …

SqlCommand only returns one row

Trying to only return the first few number of rows because my database was too big, however when I was testing my SQL, I did a select * and was only returned the first row. What is wrong with my solution? Answer In your loop you constantly re-create the instance of the variable logs thus overwriting the previ…

Using a query for Single field in Access Report

I am new to access. I have a report with a query(Q1) as its data source. Is it possible to use another query(Q2) only for one field in the same report? My main query is: My report’s structure is like this: As you can see, in the report I group my data using the Lastname column then I show details

SQL – Remove all HTML tags in a string

In my dataset, I have a field which stores text marked up with HTML. The general format is as follows: <html><head></head><body><p>My text.</p></body></html> I could attempt to solve the problem by doing the following: However, this is not a strict rule as some …