Files
MyGoNavi/internal/db/mysql_impl.go
杨国锋 0ab10d2e80 feat(query): 支持多条SQL语句执行返回多结果集
- 新增 ResultSetData 结构体承载单个结果集数据
- 新增 MultiResultQuerier/MultiResultQuerierContext 可选接口
- 新增 scanMultiRows 函数利用 NextResultSet() 遍历所有结果集
- MySQL 驱动 DSN 开启 multiStatements=true 并实现多结果集接口
- 新增 DBQueryMulti Wails 方法,支持驱动原生多结果集及自动回退逐条执行
- 新增 Go 版 SQL 拆分函数 splitSQLStatements 及 10 个单元测试
- 前端 QueryEditor handleRun 改为一次性调用 DBQueryMulti
- MongoDB 保持独立的逐条执行路径不受影响
- refs #235
2026-03-17 22:21:49 +08:00

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package db
import (
"context"
"database/sql"
"encoding/json"
"fmt"
"net/url"
"strconv"
"strings"
"time"
"GoNavi-Wails/internal/connection"
"GoNavi-Wails/internal/logger"
"GoNavi-Wails/internal/ssh"
"GoNavi-Wails/internal/utils"
_ "github.com/go-sql-driver/mysql"
)
type MySQLDB struct {
conn *sql.DB
pingTimeout time.Duration
}
const defaultMySQLPort = 3306
func parseHostPortWithDefault(raw string, defaultPort int) (string, int, bool) {
text := strings.TrimSpace(raw)
if text == "" {
return "", 0, false
}
if strings.HasPrefix(text, "[") {
end := strings.Index(text, "]")
if end < 0 {
return text, defaultPort, true
}
host := text[1:end]
portText := strings.TrimSpace(text[end+1:])
if strings.HasPrefix(portText, ":") {
if p, err := strconv.Atoi(strings.TrimSpace(strings.TrimPrefix(portText, ":"))); err == nil && p > 0 {
return host, p, true
}
}
return host, defaultPort, true
}
lastColon := strings.LastIndex(text, ":")
if lastColon > 0 && strings.Count(text, ":") == 1 {
host := strings.TrimSpace(text[:lastColon])
portText := strings.TrimSpace(text[lastColon+1:])
if host != "" {
if p, err := strconv.Atoi(portText); err == nil && p > 0 {
return host, p, true
}
return host, defaultPort, true
}
}
return text, defaultPort, true
}
func normalizeMySQLAddress(host string, port int) string {
h := strings.TrimSpace(host)
if h == "" {
h = "localhost"
}
p := port
if p <= 0 {
p = defaultMySQLPort
}
return fmt.Sprintf("%s:%d", h, p)
}
func applyMySQLURI(config connection.ConnectionConfig) connection.ConnectionConfig {
uriText := strings.TrimSpace(config.URI)
if uriText == "" {
return config
}
lowerURI := strings.ToLower(uriText)
if !strings.HasPrefix(lowerURI, "mysql://") {
return config
}
parsed, err := url.Parse(uriText)
if err != nil {
return config
}
if parsed.User != nil {
if config.User == "" {
config.User = parsed.User.Username()
}
if pass, ok := parsed.User.Password(); ok && config.Password == "" {
config.Password = pass
}
}
if dbName := strings.TrimPrefix(parsed.Path, "/"); dbName != "" && config.Database == "" {
config.Database = dbName
}
defaultPort := config.Port
if defaultPort <= 0 {
defaultPort = defaultMySQLPort
}
hostsFromURI := make([]string, 0, 4)
hostText := strings.TrimSpace(parsed.Host)
if hostText != "" {
for _, entry := range strings.Split(hostText, ",") {
host, port, ok := parseHostPortWithDefault(entry, defaultPort)
if !ok {
continue
}
hostsFromURI = append(hostsFromURI, normalizeMySQLAddress(host, port))
}
}
if len(config.Hosts) == 0 && len(hostsFromURI) > 0 {
config.Hosts = hostsFromURI
}
if strings.TrimSpace(config.Host) == "" && len(hostsFromURI) > 0 {
host, port, ok := parseHostPortWithDefault(hostsFromURI[0], defaultPort)
if ok {
config.Host = host
config.Port = port
}
}
if config.Topology == "" {
topology := strings.TrimSpace(parsed.Query().Get("topology"))
if topology != "" {
config.Topology = strings.ToLower(topology)
}
}
return config
}
func collectMySQLAddresses(config connection.ConnectionConfig) []string {
defaultPort := config.Port
if defaultPort <= 0 {
defaultPort = defaultMySQLPort
}
candidates := make([]string, 0, len(config.Hosts)+1)
if len(config.Hosts) > 0 {
candidates = append(candidates, config.Hosts...)
} else {
candidates = append(candidates, normalizeMySQLAddress(config.Host, defaultPort))
}
result := make([]string, 0, len(candidates))
seen := make(map[string]struct{}, len(candidates))
for _, entry := range candidates {
host, port, ok := parseHostPortWithDefault(entry, defaultPort)
if !ok {
continue
}
normalized := normalizeMySQLAddress(host, port)
if _, exists := seen[normalized]; exists {
continue
}
seen[normalized] = struct{}{}
result = append(result, normalized)
}
return result
}
func (m *MySQLDB) getDSN(config connection.ConnectionConfig) (string, error) {
database := config.Database
protocol := "tcp"
address := normalizeMySQLAddress(config.Host, config.Port)
if config.UseSSH {
netName, err := ssh.RegisterSSHNetwork(config.SSH)
if err != nil {
return "", fmt.Errorf("创建 SSH 隧道失败:%w", err)
}
protocol = netName
}
timeout := getConnectTimeoutSeconds(config)
tlsMode := resolveMySQLTLSMode(config)
return fmt.Sprintf(
"%s:%s@%s(%s)/%s?charset=utf8mb4&parseTime=True&loc=Local&timeout=%ds&tls=%s&multiStatements=true",
config.User, config.Password, protocol, address, database, timeout, url.QueryEscape(tlsMode),
), nil
}
func resolveMySQLCredential(config connection.ConnectionConfig, addressIndex int) (string, string) {
primaryUser := strings.TrimSpace(config.User)
primaryPassword := config.Password
replicaUser := strings.TrimSpace(config.MySQLReplicaUser)
replicaPassword := config.MySQLReplicaPassword
if addressIndex > 0 && replicaUser != "" {
return replicaUser, replicaPassword
}
if primaryUser == "" && replicaUser != "" {
return replicaUser, replicaPassword
}
return config.User, primaryPassword
}
func (m *MySQLDB) Connect(config connection.ConnectionConfig) error {
runConfig := applyMySQLURI(config)
addresses := collectMySQLAddresses(runConfig)
if len(addresses) == 0 {
return fmt.Errorf("连接建立后验证失败:未找到可用的 MySQL 地址")
}
var errorDetails []string
for index, address := range addresses {
candidateConfig := runConfig
host, port, ok := parseHostPortWithDefault(address, defaultMySQLPort)
if !ok {
continue
}
candidateConfig.Host = host
candidateConfig.Port = port
candidateConfig.User, candidateConfig.Password = resolveMySQLCredential(runConfig, index)
dsn, err := m.getDSN(candidateConfig)
if err != nil {
errorDetails = append(errorDetails, fmt.Sprintf("%s 生成连接串失败: %v", address, err))
continue
}
db, err := sql.Open("mysql", dsn)
if err != nil {
errorDetails = append(errorDetails, fmt.Sprintf("%s 打开失败: %v", address, err))
continue
}
timeout := getConnectTimeout(candidateConfig)
ctx, cancel := utils.ContextWithTimeout(timeout)
pingErr := db.PingContext(ctx)
cancel()
if pingErr != nil {
_ = db.Close()
errorDetails = append(errorDetails, fmt.Sprintf("%s 验证失败: %v", address, pingErr))
continue
}
m.conn = db
m.pingTimeout = timeout
return nil
}
if len(errorDetails) == 0 {
return fmt.Errorf("连接建立后验证失败:未找到可用的 MySQL 地址")
}
return fmt.Errorf("连接建立后验证失败:%s", strings.Join(errorDetails, ""))
}
func (m *MySQLDB) Close() error {
if m.conn != nil {
return m.conn.Close()
}
return nil
}
func (m *MySQLDB) Ping() error {
if m.conn == nil {
return fmt.Errorf("连接未打开")
}
timeout := m.pingTimeout
if timeout <= 0 {
timeout = 5 * time.Second
}
ctx, cancel := utils.ContextWithTimeout(timeout)
defer cancel()
return m.conn.PingContext(ctx)
}
func (m *MySQLDB) QueryMulti(query string) ([]connection.ResultSetData, error) {
if m.conn == nil {
return nil, fmt.Errorf("连接未打开")
}
rows, err := m.conn.Query(query)
if err != nil {
return nil, err
}
defer rows.Close()
return scanMultiRows(rows)
}
func (m *MySQLDB) QueryMultiContext(ctx context.Context, query string) ([]connection.ResultSetData, error) {
if m.conn == nil {
return nil, fmt.Errorf("连接未打开")
}
rows, err := m.conn.QueryContext(ctx, query)
if err != nil {
return nil, err
}
defer rows.Close()
return scanMultiRows(rows)
}
func (m *MySQLDB) QueryContext(ctx context.Context, query string) ([]map[string]interface{}, []string, error) {
if m.conn == nil {
return nil, nil, fmt.Errorf("连接未打开")
}
rows, err := m.conn.QueryContext(ctx, query)
if err != nil {
return nil, nil, err
}
defer rows.Close()
return scanRows(rows)
}
func (m *MySQLDB) Query(query string) ([]map[string]interface{}, []string, error) {
if m.conn == nil {
return nil, nil, fmt.Errorf("连接未打开")
}
rows, err := m.conn.Query(query)
if err != nil {
return nil, nil, err
}
defer rows.Close()
return scanRows(rows)
}
func (m *MySQLDB) ExecContext(ctx context.Context, query string) (int64, error) {
if m.conn == nil {
return 0, fmt.Errorf("连接未打开")
}
res, err := m.conn.ExecContext(ctx, query)
if err != nil {
return 0, err
}
return res.RowsAffected()
}
func (m *MySQLDB) Exec(query string) (int64, error) {
if m.conn == nil {
return 0, fmt.Errorf("连接未打开")
}
res, err := m.conn.Exec(query)
if err != nil {
return 0, err
}
return res.RowsAffected()
}
func (m *MySQLDB) GetDatabases() ([]string, error) {
data, _, err := m.Query("SHOW DATABASES")
if err != nil {
return nil, err
}
var dbs []string
for _, row := range data {
if val, ok := row["Database"]; ok {
dbs = append(dbs, fmt.Sprintf("%v", val))
} else if val, ok := row["database"]; ok {
dbs = append(dbs, fmt.Sprintf("%v", val))
}
}
return dbs, nil
}
func (m *MySQLDB) GetTables(dbName string) ([]string, error) {
query := "SHOW TABLES"
if dbName != "" {
query = fmt.Sprintf("SHOW TABLES FROM `%s`", dbName)
}
data, _, err := m.Query(query)
if err != nil {
return nil, err
}
var tables []string
for _, row := range data {
for _, v := range row {
tables = append(tables, fmt.Sprintf("%v", v))
break
}
}
return tables, nil
}
func (m *MySQLDB) GetCreateStatement(dbName, tableName string) (string, error) {
query := fmt.Sprintf("SHOW CREATE TABLE `%s`.`%s`", dbName, tableName)
if dbName == "" {
query = fmt.Sprintf("SHOW CREATE TABLE `%s`", tableName)
}
data, _, err := m.Query(query)
if err != nil {
return "", err
}
if len(data) > 0 {
if val, ok := data[0]["Create Table"]; ok {
return fmt.Sprintf("%v", val), nil
}
}
return "", fmt.Errorf("未找到建表语句")
}
func (m *MySQLDB) GetColumns(dbName, tableName string) ([]connection.ColumnDefinition, error) {
query := fmt.Sprintf("SHOW FULL COLUMNS FROM `%s`.`%s`", dbName, tableName)
if dbName == "" {
query = fmt.Sprintf("SHOW FULL COLUMNS FROM `%s`", tableName)
}
data, _, err := m.Query(query)
if err != nil {
return nil, err
}
var columns []connection.ColumnDefinition
for _, row := range data {
col := connection.ColumnDefinition{
Name: fmt.Sprintf("%v", row["Field"]),
Type: fmt.Sprintf("%v", row["Type"]),
Nullable: fmt.Sprintf("%v", row["Null"]),
Key: fmt.Sprintf("%v", row["Key"]),
Extra: fmt.Sprintf("%v", row["Extra"]),
Comment: fmt.Sprintf("%v", row["Comment"]),
}
if row["Default"] != nil {
d := fmt.Sprintf("%v", row["Default"])
col.Default = &d
}
columns = append(columns, col)
}
return columns, nil
}
func (m *MySQLDB) GetIndexes(dbName, tableName string) ([]connection.IndexDefinition, error) {
query := fmt.Sprintf("SHOW INDEX FROM `%s`.`%s`", dbName, tableName)
if dbName == "" {
query = fmt.Sprintf("SHOW INDEX FROM `%s`", tableName)
}
data, _, err := m.Query(query)
if err != nil {
return nil, err
}
var indexes []connection.IndexDefinition
for _, row := range data {
nonUnique := 0
if val, ok := row["Non_unique"]; ok {
if f, ok := val.(float64); ok {
nonUnique = int(f)
} else if i, ok := val.(int64); ok {
nonUnique = int(i)
}
}
seq := 0
if val, ok := row["Seq_in_index"]; ok {
if f, ok := val.(float64); ok {
seq = int(f)
} else if i, ok := val.(int64); ok {
seq = int(i)
}
}
subPart := 0
if val, ok := row["Sub_part"]; ok && val != nil {
if f, ok := val.(float64); ok {
subPart = int(f)
} else if i, ok := val.(int64); ok {
subPart = int(i)
}
}
idx := connection.IndexDefinition{
Name: fmt.Sprintf("%v", row["Key_name"]),
ColumnName: fmt.Sprintf("%v", row["Column_name"]),
NonUnique: nonUnique,
SeqInIndex: seq,
IndexType: fmt.Sprintf("%v", row["Index_type"]),
SubPart: subPart,
}
indexes = append(indexes, idx)
}
return indexes, nil
}
func (m *MySQLDB) GetForeignKeys(dbName, tableName string) ([]connection.ForeignKeyDefinition, error) {
query := fmt.Sprintf(`SELECT CONSTRAINT_NAME, COLUMN_NAME, REFERENCED_TABLE_NAME, REFERENCED_COLUMN_NAME
FROM information_schema.KEY_COLUMN_USAGE
WHERE TABLE_SCHEMA = '%s' AND TABLE_NAME = '%s' AND REFERENCED_TABLE_NAME IS NOT NULL`, dbName, tableName)
data, _, err := m.Query(query)
if err != nil {
return nil, err
}
var fks []connection.ForeignKeyDefinition
for _, row := range data {
fk := connection.ForeignKeyDefinition{
Name: fmt.Sprintf("%v", row["CONSTRAINT_NAME"]),
ColumnName: fmt.Sprintf("%v", row["COLUMN_NAME"]),
RefTableName: fmt.Sprintf("%v", row["REFERENCED_TABLE_NAME"]),
RefColumnName: fmt.Sprintf("%v", row["REFERENCED_COLUMN_NAME"]),
ConstraintName: fmt.Sprintf("%v", row["CONSTRAINT_NAME"]),
}
fks = append(fks, fk)
}
return fks, nil
}
func (m *MySQLDB) GetTriggers(dbName, tableName string) ([]connection.TriggerDefinition, error) {
query := fmt.Sprintf("SHOW TRIGGERS FROM `%s` WHERE `Table` = '%s'", dbName, tableName)
data, _, err := m.Query(query)
if err != nil {
return nil, err
}
var triggers []connection.TriggerDefinition
for _, row := range data {
trig := connection.TriggerDefinition{
Name: fmt.Sprintf("%v", row["Trigger"]),
Timing: fmt.Sprintf("%v", row["Timing"]),
Event: fmt.Sprintf("%v", row["Event"]),
Statement: fmt.Sprintf("%v", row["Statement"]),
}
triggers = append(triggers, trig)
}
return triggers, nil
}
func (m *MySQLDB) ApplyChanges(tableName string, changes connection.ChangeSet) error {
if m.conn == nil {
return fmt.Errorf("连接未打开")
}
columnTypeMap := m.loadColumnTypeMap(tableName)
tx, err := m.conn.Begin()
if err != nil {
return err
}
defer tx.Rollback()
// 1. Deletes
for _, pk := range changes.Deletes {
var wheres []string
var args []interface{}
for k, v := range pk {
wheres = append(wheres, fmt.Sprintf("`%s` = ?", k))
args = append(args, normalizeMySQLValueForWrite(k, v, columnTypeMap))
}
if len(wheres) == 0 {
continue
}
query := fmt.Sprintf("DELETE FROM `%s` WHERE %s", tableName, strings.Join(wheres, " AND "))
res, err := tx.Exec(query, args...)
if err != nil {
return fmt.Errorf("删除失败:%v", err)
}
if affected, err := res.RowsAffected(); err == nil && affected == 0 {
return fmt.Errorf("删除未生效:未匹配到任何行")
}
}
// 2. Updates
for _, update := range changes.Updates {
var sets []string
var args []interface{}
for k, v := range update.Values {
sets = append(sets, fmt.Sprintf("`%s` = ?", k))
args = append(args, normalizeMySQLValueForWrite(k, v, columnTypeMap))
}
if len(sets) == 0 {
continue
}
var wheres []string
for k, v := range update.Keys {
wheres = append(wheres, fmt.Sprintf("`%s` = ?", k))
args = append(args, normalizeMySQLValueForWrite(k, v, columnTypeMap))
}
if len(wheres) == 0 {
return fmt.Errorf("更新操作需要主键条件")
}
query := fmt.Sprintf("UPDATE `%s` SET %s WHERE %s", tableName, strings.Join(sets, ", "), strings.Join(wheres, " AND "))
res, err := tx.Exec(query, args...)
if err != nil {
return fmt.Errorf("更新失败:%v", err)
}
if affected, err := res.RowsAffected(); err == nil && affected == 0 {
return fmt.Errorf("更新未生效:未匹配到任何行")
}
}
// 3. Inserts
for _, row := range changes.Inserts {
var cols []string
var placeholders []string
var args []interface{}
for k, v := range row {
normalizedValue, omit := normalizeMySQLValueForInsert(k, v, columnTypeMap)
if omit {
continue
}
cols = append(cols, fmt.Sprintf("`%s`", k))
placeholders = append(placeholders, "?")
args = append(args, normalizedValue)
}
if len(cols) == 0 {
query := fmt.Sprintf("INSERT INTO `%s` () VALUES ()", tableName)
res, err := tx.Exec(query)
if err != nil {
return fmt.Errorf("插入失败:%v", err)
}
if affected, err := res.RowsAffected(); err == nil && affected == 0 {
return fmt.Errorf("插入未生效:未影响任何行")
}
continue
}
query := fmt.Sprintf("INSERT INTO `%s` (%s) VALUES (%s)", tableName, strings.Join(cols, ", "), strings.Join(placeholders, ", "))
res, err := tx.Exec(query, args...)
if err != nil {
return fmt.Errorf("插入失败:%v", err)
}
if affected, err := res.RowsAffected(); err == nil && affected == 0 {
return fmt.Errorf("插入未生效:未影响任何行")
}
}
return tx.Commit()
}
func normalizeMySQLComplexValue(value interface{}) interface{} {
switch v := value.(type) {
case map[string]interface{}, []interface{}:
if data, err := json.Marshal(v); err == nil {
return string(data)
}
return fmt.Sprintf("%v", value)
default:
return value
}
}
func normalizeMySQLDateTimeValue(value interface{}) interface{} {
text, ok := value.(string)
if !ok {
return value
}
raw := strings.TrimSpace(text)
if raw == "" {
return value
}
cleaned := strings.ReplaceAll(raw, "+ ", "+")
cleaned = strings.ReplaceAll(cleaned, "- ", "-")
if len(cleaned) >= 19 && cleaned[10] == 'T' {
if strings.HasSuffix(cleaned, "Z") || hasTimezoneOffset(cleaned) {
if t, err := time.Parse(time.RFC3339Nano, cleaned); err == nil {
return formatMySQLDateTime(t)
}
if t, err := time.Parse(time.RFC3339, cleaned); err == nil {
return formatMySQLDateTime(t)
}
}
return strings.Replace(cleaned, "T", " ", 1)
}
if strings.Contains(cleaned, " ") && (strings.HasSuffix(cleaned, "Z") || hasTimezoneOffset(cleaned)) {
candidate := strings.Replace(cleaned, " ", "T", 1)
if t, err := time.Parse(time.RFC3339Nano, candidate); err == nil {
return formatMySQLDateTime(t)
}
if t, err := time.Parse(time.RFC3339, candidate); err == nil {
return formatMySQLDateTime(t)
}
}
return value
}
func (m *MySQLDB) loadColumnTypeMap(tableName string) map[string]string {
result := map[string]string{}
table := strings.TrimSpace(tableName)
if table == "" {
return result
}
columns, err := m.GetColumns("", table)
if err != nil {
logger.Warnf("加载列元数据失败(不影响提交):表=%s err=%v", table, err)
return result
}
for _, col := range columns {
name := strings.ToLower(strings.TrimSpace(col.Name))
if name == "" {
continue
}
result[name] = strings.TrimSpace(col.Type)
}
return result
}
func normalizeMySQLValueForInsert(columnName string, value interface{}, columnTypeMap map[string]string) (interface{}, bool) {
columnType := strings.ToLower(strings.TrimSpace(columnTypeMap[strings.ToLower(strings.TrimSpace(columnName))]))
if !isMySQLTemporalColumnType(columnType) {
return normalizeMySQLComplexValue(value), false
}
text, ok := value.(string)
if ok && strings.TrimSpace(text) == "" {
// INSERT 空时间字段不写入,交给 DB 默认值处理(如 CURRENT_TIMESTAMP
return nil, true
}
return normalizeMySQLDateTimeValue(value), false
}
func normalizeMySQLValueForWrite(columnName string, value interface{}, columnTypeMap map[string]string) interface{} {
columnType := strings.ToLower(strings.TrimSpace(columnTypeMap[strings.ToLower(strings.TrimSpace(columnName))]))
if !isMySQLTemporalColumnType(columnType) {
return value
}
text, ok := value.(string)
if ok && strings.TrimSpace(text) == "" {
return nil
}
return normalizeMySQLDateTimeValue(value)
}
func isMySQLTemporalColumnType(columnType string) bool {
raw := strings.ToLower(strings.TrimSpace(columnType))
if raw == "" {
return false
}
if strings.Contains(raw, "datetime") || strings.Contains(raw, "timestamp") {
return true
}
base := raw
if idx := strings.IndexAny(base, "( "); idx >= 0 {
base = base[:idx]
}
return base == "date" || base == "time" || base == "year"
}
func hasTimezoneOffset(text string) bool {
pos := strings.LastIndexAny(text, "+-")
if pos < 0 || pos < 10 || pos+1 >= len(text) {
return false
}
offset := text[pos+1:]
if len(offset) == 5 && offset[2] == ':' {
return isAllDigits(offset[:2]) && isAllDigits(offset[3:])
}
if len(offset) == 4 {
return isAllDigits(offset)
}
return false
}
func isAllDigits(text string) bool {
if text == "" {
return false
}
for _, r := range text {
if r < '0' || r > '9' {
return false
}
}
return true
}
func formatMySQLDateTime(t time.Time) string {
base := t.Format("2006-01-02 15:04:05")
nanos := t.Nanosecond()
if nanos == 0 {
return base
}
micro := nanos / 1000
return fmt.Sprintf("%s.%06d", base, micro)
}
func (m *MySQLDB) GetAllColumns(dbName string) ([]connection.ColumnDefinitionWithTable, error) {
query := fmt.Sprintf("SELECT TABLE_NAME, COLUMN_NAME, COLUMN_TYPE FROM information_schema.COLUMNS WHERE TABLE_SCHEMA = '%s'", dbName)
if dbName == "" {
return nil, fmt.Errorf("获取全部列信息需要指定数据库名称")
}
data, _, err := m.Query(query)
if err != nil {
return nil, err
}
var cols []connection.ColumnDefinitionWithTable
for _, row := range data {
col := connection.ColumnDefinitionWithTable{
TableName: fmt.Sprintf("%v", row["TABLE_NAME"]),
Name: fmt.Sprintf("%v", row["COLUMN_NAME"]),
Type: fmt.Sprintf("%v", row["COLUMN_TYPE"]),
}
cols = append(cols, col)
}
return cols, nil
}