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A comment on We saved $50k/year with a Go microservice coded in a hackathon. Parent comment

Re:We saved $50k/year with a Go microservice coded in a hack... by ThrustVectoring on Tuesday April 10, 2018 @08:51PM (#16807136)
The UI they showed in the blog post looks like it has enough data available to generate that kind of query, too. Like, the ands/ors/nots are right there on the page, the filters are already there too getting translated to SQL as well, just mash them together and you get the same "algebra of sets" stuff right in the WHERE clause.

As it stands the SQL query is quite silly. It gets a list of every user ID that is included by each filter and compares which ones are in the filters you want and not the filters you don't want. Much better is to pass the filters into SQL, let it figure out which users match the filters you want and not the filters you don't, and just use that result.

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Re:We saved $50k/year with a Go microservice coded in a hack... by jwatte on Tuesday April 10, 2018 @10:24PM (#16807549)
Most Enterprise CRM like solutions store tables of customer-property-value instead of using one column per property.

This leads to lots of unions in advanced queries, and makes filtering harder. Some databases even calculate column block statistics to optimize these queries by doing less IO even for seeming table scans.

Why not one table with all customers and one column per property? There are a few reasons, having to do with anything from MySQL sucking at schema alters for really big tables, to expectations of Enterprise customers.

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