refactor(database): sql query builder

[MR2011]

Task Description

SQL queries are created by string parsing in Heureka. This is error prone and makes it difficult to maintain. Instead a SQL Query Builder should be used.

Action Items

• Research potential tools
• Implement for one Example (e.g. Service SQL Queries)

[aditi-agrawal12]

Hi! I'd like to work on this issue.
I plan to evaluate SQL query builders for Go and implement one example using Squirrel.
Could you please assign it to me?