Table index size, what does it affect?

Question

MySQL

There is a table storing a large amount of data (tens of millions of records). To speed up selections from it, I decided to set up partitioning, because. typical queries allow this to be done conveniently (95% of queries will only require data from the 1st partition).
Stumbled upon the mysql requirement - the field by which we partition must be included in all indexes and all unique keys of the table. Nowhere to go, he added. As a result, now the table has several indexes, each of which includes from 2 to 4 fields. Already now the size of the index is about 2 times the size of the table. Can this negatively affect the performance of working with it?

Answer 1

Maybe, after all, you also need to search for indexes, and if it is very large, then it will take longer to search among very large data.

Answer 2

Indexes must be allocated in memory. Each new index is a delay in adding/updating information.

Answer 3

Depends on the type of table access. If there are more reads than records, then it shouldn't.
If the table is actively written, deleted, changed, then you need to think about how to reduce the number of indexes.