What types of data structures can be used to implement data indexing?

The following data structures are often used for data indexing in programming:

• Hash tables (Hash maps) — provide fast access by key, usually with amortized time O(1).
• Trees (e.g., binary search trees, B-trees) — allow storing data in sorted order and performing efficient search, insertion, and deletion.
• Trie (prefix tree) — used for string indexing and prefix search.
• Skip list — a probabilistic data structure that provides logarithmic time for search and insertion.

Example of using a hash table in Go:

package main

import "fmt"

func main() {
    index := make(map[string]int)
    index["apple"] = 1
    index["banana"] = 2

    fmt.Println(index["apple"]) // Output: 1
}