使用原生的Golang进行数据库CRUD感觉到诸多不变，于是参照之前使用数据库类的习惯用法，
封装了一个数据库操作方法集：
package lib
import (
"database/sql"
_ "github.com/go-sql-driver/mysql"
"strings"
"fmt"
)
type dbRow map[string]interface{}
type Dblib struct {
db *sql.DB
}
func NewDblib(driver, dsn string) (*Dblib, error) {
db, err := sql.Open(driver, dsn)
if err != nil {
return nil, err
}
err = db.Ping()
if err != nil {
return nil, err
}
p := new(Dblib)
p.db = db
return p, nil
}
func scanRow(rows *sql.Rows) (dbRow, error) {
columns, _ := rows.Columns()
vals := make([]interface{}, len(columns))
valsPtr := make([]interface{}, len(columns))
for i := range vals {
valsPtr[i] = &vals[i]
}
err := rows.Scan(valsPtr...)
if err != nil {
return nil ,err
}
r := make(dbRow)
for i, v := range columns {
if va, ok := vals[i].([]byte); ok {
r[v] = string(va)
} else {
r[v] = vals[i]
}
}
return r, nil
}
// 获取一行记录
func (d *Dblib) GetOne(sql string, args ...interface{}) (dbRow, error) {
rows, err := d.db.Query(sql, args...)
if err != nil {
return nil, err
}
defer rows.Close()
rows.Next()
result, err := scanRow(rows)
return result, err
}
// 获取多行记录
func (d *Dblib) GetAll(sql string, args ...interface{}) ([]dbRow, error) {
rows, err := d.db.Query(sql, args...)
if err != nil {
return nil, err
}
defer rows.Close()
result := make([]dbRow, 0)
for rows.Next() {
r, err := scanRow(rows)
if err != nil {
continue
}
result = append(result, r)
}
return result, nil
}
// 写入记录
func (d *Dblib) Insert(table string, data dbRow) (int64, error) {
fields := make([]string, 0)
vals := make([]interface{}, 0)
placeHolder := make([]string, 0)
for f, v := range data {
fields = append(fields, f)
vals = append(vals, v)
placeHolder = append(placeHolder, "?")
}
sql := fmt.Sprintf("INSERT INTO %s(%s) VALUES(%s) ", table, strings.Join(fields, ","), strings.Join(placeHolder, ","))
result, err := d.db.Exec(sql, vals...)
if err != nil {
return 0, err
}
lID, err := result.LastInsertId()
if err != nil {
return 0, err
}
return lID, nil
}
// 更新记录
func (d *Dblib) Update(table, condition string, data dbRow, args ...interface{}) (int64, error) {
params := make([]string, 0)
vals := make([]interface{}, 0)
for f, v := range data {
params = append(params, f + "=?")
vals = append(vals, v)
}
sql := "UPDATE %s SET %s"
if condition != "" {
sql += " WHERE %s"
sql = fmt.Sprintf(sql, table, strings.Join(params, ","), condition)
vals = append(vals, args...)
} else {
sql = fmt.Sprintf(sql, table, strings.Join(params, ","))
}
result, err := d.db.Exec(sql, vals...)
if err != nil {
return 0, err
}
aID, err := result.RowsAffected()
if err != nil {
return 0, err
}
return aID, nil
}
// 删除记录
func (d *Dblib) Delete(table, condition string, args ...interface{}) (int64, error) {
sql := "DELETE FROM %s "
if condition != "" {
sql += "WHERE %s"
sql = fmt.Sprintf(sql, table, condition)
} else {
sql = fmt.Sprintf(sql, table)
}
result, err := d.db.Exec(sql, args...)
if err != nil {
return 0, err
}
aID, err := result.RowsAffected()
if err != nil {
return 0, err
}
return aID, nil
}