@razumilovs You're right flat tables are fast to search.
But flat tables are always (at least in my experience) used as a workaround and as the last option to get performance gain.
Most of the time they're non-relational in nature hence they come up with more headaches than benefits.
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@razumilovs You can't call it a tip!
Most of the time flat tables are the end result of a poor DB design/normalization.
That's why it's important to normalize your DB properly so that you don't have to reach that state where you've to create flat tables.
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@razumilovs Normalization Benefits:
1. Helps reduce data redundancy - reduces duplicate data, reduces table size.
2. Helps in a logical grouping of data into multiple tables, and reduces the size of the table.
3. You always work with a small group of data. Hence fewer data to fetch.
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@razumilovs Normalization is good for all types of query insert, update, delete, and select queries. The same flat table could be good for selection but might not be good for other operations so that's why choosing a flat table is always a tricky process.
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@razumilovs Good normalized tables are always good, over normalized tables are bad.
Normalization has no direct relation with performance but indirectly it can give good performance if followed well.
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