How to Count Rows in a Go Database?

Counting Rows in Go

Retrieving the count of rows from a database is a fundamental operation in Go applications. One approach is to use the db.Query function to execute a raw SQL query. By setting the query to SELECT COUNT(*) FROM you can fetch the row count.

<code class="go">count, err := db.Query("SELECT COUNT(*) FROM main_table")</code>

However, you'll need to scan the returned row to access the actual count value.

<code class="go">var rowCount int
if err := rows.Scan(&rowCount); err != nil {
    log.Fatal(err)
}</code>

You can then print the rowCount:

<code class="go">fmt.Printf("Number of rows are %s\n", rowCount)</code>

For simplicity, it's recommended to use db.QueryRow instead of db.Query in this scenario, as you expect only one row to be returned.

<code class="go">var rowCount int
err := db.QueryRow("SELECT COUNT(*) FROM main_table").Scan(&rowCount)</code>

By using QueryRow(), you can avoid closing the result and handle the error gracefully using switch:

<code class="go">switch {
case err != nil:
    log.Fatal(err)
default:
    fmt.Printf("Number of rows are %s\n", rowCount)
}</code>

This provides a concise and efficient way to retrieve row counts from a database in Go.

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