有人知道一个快速简单的方法来迁移SQLite3数据库到MySQL吗?
当前回答
我用Python3编写了这个简单的脚本。它可以作为包含的类或通过终端shell调用的独立脚本使用。默认情况下,它将所有整数导入为int(11),将字符串导入为varchar(300),但所有这些都可以分别在构造函数或脚本参数中进行调整。
注意:它需要MySQL连接器/Python 2.0.4或更高版本
如果你觉得下面的代码很难阅读,这是GitHub上的源代码链接:https://github.com/techouse/sqlite3-to-mysql
#!/usr/bin/env python3
__author__ = "Klemen Tušar"
__email__ = "techouse@gmail.com"
__copyright__ = "GPL"
__version__ = "1.0.1"
__date__ = "2015-09-12"
__status__ = "Production"
import os.path, sqlite3, mysql.connector
from mysql.connector import errorcode
class SQLite3toMySQL:
"""
Use this class to transfer an SQLite 3 database to MySQL.
NOTE: Requires MySQL Connector/Python 2.0.4 or higher (https://dev.mysql.com/downloads/connector/python/)
"""
def __init__(self, **kwargs):
self._properties = kwargs
self._sqlite_file = self._properties.get('sqlite_file', None)
if not os.path.isfile(self._sqlite_file):
print('SQLite file does not exist!')
exit(1)
self._mysql_user = self._properties.get('mysql_user', None)
if self._mysql_user is None:
print('Please provide a MySQL user!')
exit(1)
self._mysql_password = self._properties.get('mysql_password', None)
if self._mysql_password is None:
print('Please provide a MySQL password')
exit(1)
self._mysql_database = self._properties.get('mysql_database', 'transfer')
self._mysql_host = self._properties.get('mysql_host', 'localhost')
self._mysql_integer_type = self._properties.get('mysql_integer_type', 'int(11)')
self._mysql_string_type = self._properties.get('mysql_string_type', 'varchar(300)')
self._sqlite = sqlite3.connect(self._sqlite_file)
self._sqlite.row_factory = sqlite3.Row
self._sqlite_cur = self._sqlite.cursor()
self._mysql = mysql.connector.connect(
user=self._mysql_user,
password=self._mysql_password,
host=self._mysql_host
)
self._mysql_cur = self._mysql.cursor(prepared=True)
try:
self._mysql.database = self._mysql_database
except mysql.connector.Error as err:
if err.errno == errorcode.ER_BAD_DB_ERROR:
self._create_database()
else:
print(err)
exit(1)
def _create_database(self):
try:
self._mysql_cur.execute("CREATE DATABASE IF NOT EXISTS `{}` DEFAULT CHARACTER SET 'utf8'".format(self._mysql_database))
self._mysql_cur.close()
self._mysql.commit()
self._mysql.database = self._mysql_database
self._mysql_cur = self._mysql.cursor(prepared=True)
except mysql.connector.Error as err:
print('_create_database failed creating databse {}: {}'.format(self._mysql_database, err))
exit(1)
def _create_table(self, table_name):
primary_key = ''
sql = 'CREATE TABLE IF NOT EXISTS `{}` ( '.format(table_name)
self._sqlite_cur.execute('PRAGMA table_info("{}")'.format(table_name))
for row in self._sqlite_cur.fetchall():
column = dict(row)
sql += ' `{name}` {type} {notnull} {auto_increment}, '.format(
name=column['name'],
type=self._mysql_string_type if column['type'].upper() == 'TEXT' else self._mysql_integer_type,
notnull='NOT NULL' if column['notnull'] else 'NULL',
auto_increment='AUTO_INCREMENT' if column['pk'] else ''
)
if column['pk']:
primary_key = column['name']
sql += ' PRIMARY KEY (`{}`) ) ENGINE = InnoDB CHARACTER SET utf8'.format(primary_key)
try:
self._mysql_cur.execute(sql)
self._mysql.commit()
except mysql.connector.Error as err:
print('_create_table failed creating table {}: {}'.format(table_name, err))
exit(1)
def transfer(self):
self._sqlite_cur.execute("SELECT name FROM sqlite_master WHERE type='table' AND name NOT LIKE 'sqlite_%'")
for row in self._sqlite_cur.fetchall():
table = dict(row)
# create the table
self._create_table(table['name'])
# populate it
print('Transferring table {}'.format(table['name']))
self._sqlite_cur.execute('SELECT * FROM "{}"'.format(table['name']))
columns = [column[0] for column in self._sqlite_cur.description]
try:
self._mysql_cur.executemany("INSERT IGNORE INTO `{table}` ({fields}) VALUES ({placeholders})".format(
table=table['name'],
fields=('`{}`, ' * len(columns)).rstrip(' ,').format(*columns),
placeholders=('%s, ' * len(columns)).rstrip(' ,')
), (tuple(data) for data in self._sqlite_cur.fetchall()))
self._mysql.commit()
except mysql.connector.Error as err:
print('_insert_table_data failed inserting data into table {}: {}'.format(table['name'], err))
exit(1)
print('Done!')
def main():
""" For use in standalone terminal form """
import sys, argparse
parser = argparse.ArgumentParser()
parser.add_argument('--sqlite-file', dest='sqlite_file', default=None, help='SQLite3 db file')
parser.add_argument('--mysql-user', dest='mysql_user', default=None, help='MySQL user')
parser.add_argument('--mysql-password', dest='mysql_password', default=None, help='MySQL password')
parser.add_argument('--mysql-database', dest='mysql_database', default=None, help='MySQL host')
parser.add_argument('--mysql-host', dest='mysql_host', default='localhost', help='MySQL host')
parser.add_argument('--mysql-integer-type', dest='mysql_integer_type', default='int(11)', help='MySQL default integer field type')
parser.add_argument('--mysql-string-type', dest='mysql_string_type', default='varchar(300)', help='MySQL default string field type')
args = parser.parse_args()
if len(sys.argv) == 1:
parser.print_help()
exit(1)
converter = SQLite3toMySQL(
sqlite_file=args.sqlite_file,
mysql_user=args.mysql_user,
mysql_password=args.mysql_password,
mysql_database=args.mysql_database,
mysql_host=args.mysql_host,
mysql_integer_type=args.mysql_integer_type,
mysql_string_type=args.mysql_string_type
)
converter.transfer()
if __name__ == '__main__':
main()
其他回答
这个简单的解决方案对我很有效:
<?php
$sq = new SQLite3( 'sqlite3.db' );
$tables = $sq->query( 'SELECT name FROM sqlite_master WHERE type="table"' );
while ( $table = $tables->fetchArray() ) {
$table = current( $table );
$result = $sq->query( sprintf( 'SELECT * FROM %s', $table ) );
if ( strpos( $table, 'sqlite' ) !== false )
continue;
printf( "-- %s\n", $table );
while ( $row = $result->fetchArray( SQLITE3_ASSOC ) ) {
$values = array_map( function( $value ) {
return sprintf( "'%s'", mysql_real_escape_string( $value ) );
}, array_values( $row ) );
printf( "INSERT INTO `%s` VALUES( %s );\n", $table, implode( ', ', $values ) );
}
}
获取SQL转储
moose@pc08$ sqlite3 mySqliteDatabase.db .dump > myTemporarySQLFile.sql
导入转储到MySQL
小批量进口:
moose@pc08$ mysql -u <username> -p
Enter password:
....
mysql> use somedb;
Database changed
mysql> source myTemporarySQLFile.sql;
or
mysql -u root -p somedb < myTemporarySQLFile.sql
这将提示您输入密码。请注意:如果你想直接输入你的密码,你必须不带空格,直接在-p后输入:
mysql -u root -pYOURPASS somedb < myTemporarySQLFile.sql
对于较大的转储:
mysqlimport或其他导入工具,如BigDump。
BigDump给你一个进度条:
我通常使用IntelliJ DataGrip的导出/导入表功能。
您可以在右下角看到进度。
[]
每个人似乎都是从一些grep和perl表达式开始的,你可能会得到一些适用于特定数据集的东西,但你不知道它是否正确地导入了数据。我真的很惊讶没有人建立一个可靠的库,可以在两者之间转换。
这里列出了我所知道的两种文件格式之间SQL语法的所有差异: 以以下几行开头:
开始事务 提交 sqlite_sequence 创建唯一索引
在MySQL中不使用
SQLite uses CREATE TABLE/INSERT INTO "table_name" and MySQL uses CREATE TABLE/INSERT INTO table_name MySQL doesn't use quotes inside the schema definition MySQL uses single quotes for strings inside the INSERT INTO clauses SQLite and MySQL have different ways of escaping strings inside INSERT INTO clauses SQLite uses 't' and 'f' for booleans, MySQL uses 1 and 0 (a simple regex for this can fail when you have a string like: 'I do, you don't' inside your INSERT INTO) SQLLite uses AUTOINCREMENT, MySQL uses AUTO_INCREMENT
这是一个非常基本的perl脚本,它适用于我的数据集,并检查了我在网上找到的其他perl脚本的更多这些条件。Nu保证它将为您的数据工作,但请随意修改和发布回这里。
#! /usr/bin/perl
while ($line = <>){
if (($line !~ /BEGIN TRANSACTION/) && ($line !~ /COMMIT/) && ($line !~ /sqlite_sequence/) && ($line !~ /CREATE UNIQUE INDEX/)){
if ($line =~ /CREATE TABLE \"([a-z_]*)\"(.*)/i){
$name = $1;
$sub = $2;
$sub =~ s/\"//g;
$line = "DROP TABLE IF EXISTS $name;\nCREATE TABLE IF NOT EXISTS $name$sub\n";
}
elsif ($line =~ /INSERT INTO \"([a-z_]*)\"(.*)/i){
$line = "INSERT INTO $1$2\n";
$line =~ s/\"/\\\"/g;
$line =~ s/\"/\'/g;
}else{
$line =~ s/\'\'/\\\'/g;
}
$line =~ s/([^\\'])\'t\'(.)/$1THIS_IS_TRUE$2/g;
$line =~ s/THIS_IS_TRUE/1/g;
$line =~ s/([^\\'])\'f\'(.)/$1THIS_IS_FALSE$2/g;
$line =~ s/THIS_IS_FALSE/0/g;
$line =~ s/AUTOINCREMENT/AUTO_INCREMENT/g;
print $line;
}
}
最近,为了我们团队正在进行的一个项目,我不得不从MySQL迁移到JavaDB。我发现Apache编写的一个名为DdlUtils的Java库非常容易做到这一点。它提供了一个API,让你做以下事情:
发现数据库的模式并将其导出为XML文件。 根据此模式修改DB。 将记录从一个DB导入到另一个DB,假设它们具有相同的模式。
我们最终使用的工具并不是完全自动化的,但它们工作得很好。即使您的应用程序不是用Java编写的,使用一些小工具进行一次性迁移也不会太难。我认为我只用了不到150行代码就完成了迁移。