GO language – mysql query encapsulation

1. Mysql connection function

// Introduce two libraries
import (
    "database/sql"
    _ "github.com/go-sql-driver/mysql" // SQL depends on this mysql extension
)

// Create a mysql connection
func NewMysqlConn(db *sql.DB, err error) {
    db, err = sql.Open("mysql"."Root: 123456 @ TCP (127.0.0.1:3306)/test? charset=utf8")
    return
}
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Mysql > select * from ‘SQL’ where ‘Rows’ =’ map ‘;

func GetResultRow(rows *sql.Rows) map[string]string{
    columns, _ := rows.Columns()    / / to get listed
    scanArgs := make([]interface{}, len(columns))   // Populate the data
    values := make([]interface{}, len(columns)) // Store data values
    
    // Store a pointer to values in scanArgs
    for i := range values {
        scanArgs[i] = &values[i]
    }
    // The map used to hold the entire query result
    record := make(map[string]string)
    for rows.Next() {
        // Scan method assignment
        rows.Scan(scanArgs...)
        // There is a value in values because of pointer binding, traversal assigns value to record
        for i, v := range values {
            ifv ! =nil {
                record[columns[i]] = string(v.([]byte)) // An assertion is required, and then the string method is converted to a string}}}return record
}

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SQL.Rows = map[int]map[string]string

func GetResultRows(rows *sql.Rows) map[int]map[string]string {
    // Return all columns
    columns, _ := rows.Columns()
    // Identifies the values of all columns in a row, denoted by []byte
    vals := make([] []byte.len(columns))
    // This marks a row of fill data
    scans := make([]interface{}, len(columns))
    // here scans refer to vals and insert data into []byte
    for k, _ := range vals {
        scan[k] = &val[k]
    }
    i := 0
    result := make(map[int]map[string]string)
    for row.Next() {
        // Populate the data
        rows.scan(scans...)
        // Data per row
        row := make(map[string]string)
        // Assign data from VALS to row
        for k, v := range vals {
            key := columns[k]
            // Convert []byte data to string
            row[key] = string(v)
        }
        // Put the result set
        result[i] = row
        i++
    }
    return result
}
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