Sqlite数据库迁移为Mysql程序
作者：linux120 发布时间：December 8, 2012 分类：服务器维护
应需求需要将2.7G大小的sqlite迁移为Mysql，因sqlite3与mysql个别字段类型及长度不一致，导出的sql语句不能直接导入到mysql中，需要将sqlite .dump出来的sql语句用下列程序处理后再导入到mysql中，程序为python环境。
stm.py
#! /usr/bin/env python
### A python script written for SQLite migrate to Mysql by Linux120.com
import re, fileinput, tempfile
from optparse import OptionParser
IGNOREDPREFIXES = [
'PRAGMA',
'BEGIN TRANSACTION;',
'COMMIT;',
'DELETE FROM sqlite_sequence;',
'INSERT INTO "sqlite_sequence"',
]
def _replace(line):
if any(line.startswith(prefix) for prefix in IGNOREDPREFIXES):
return
line = line.replace("INTEGER PRIMARY KEY", "INTEGER AUTO_INCREMENT PRIMARY KEY")
line = line.replace("AUTOINCREMENT", "AUTO_INCREMENT")
line = line.replace("DEFAULT 't'", "DEFAULT '1'")
line = line.replace("DEFAULT 'f'", "DEFAULT '0'")
line = line.replace(",'t'", ",'1'")
line = line.replace(",'f'", ",'0'")
return line
def _backticks(line, in_string):
"""Replace double quotes by backticks outside (multiline) strings
>>> _backticks('''INSERT INTO "table" VALUES ('"string"');''', False)
('INSERT INTO `table` VALUES (\\'"string"\\');', False)
>>> _backticks('''INSERT INTO "table" VALUES ('"Heading''', False)
('INSERT INTO `table` VALUES (\\'"Heading', True)
>>> _backticks('''* "text":http://link.com''', True)
('* "text":http://link.com', True)
>>> _backticks(" ');", True)
(" ');", False)
"""
new = ''
for c in line:
if not in_string:
if c == "'":
in_string = True
elif c == '"':
new = new + '`'
continue
elif c == "'":
in_string = False
new = new + c
return new, in_string
def _process(opts, lines):
if opts.database:
yield '''\
drop database {d};
create database {d} character set utf8;
grant all on {d}.* to {u}@'%' identified by '{p}';
use {d};\n'''.format(d=opts.database, u=opts.username, p=opts.password)
yield "SET sql_mode='NO_BACKSLASH_ESCAPES';\n"
in_string = False
for line in lines:
if not in_string:
line = _replace(line)
if line is None:
continue
line, in_string = _backticks(line, in_string)
yield line
def _removeNewline(line, in_string):
new = ''
for c in line:
if not in_string:
if c == "'":
in_string = True
elif c == "'":
in_string = False
elif in_string:
if c == "\n":
new = new + 'Newline333'
continue
if c == "\r":
new = new + 'carriagereturn333'
continue
new = new + c
return new, in_string
def _replaceNewline(lines):
for line in lines:
line = line.replace("Newline333", "\n")
line = line.replace("carriagereturn333", "\r")
yield line
def _Newline(lines):
in_string = False
for line in lines:
if line is None:
continue
line, in_string = _removeNewline(line, in_string)
yield line
def main():
op = OptionParser()
op.add_option('-d', '--database')
op.add_option('-u', '--username')
op.add_option('-p', '--password')
opts, args = op.parse_args()
lines = (l for l in fileinput.input(args))
lines = (l for l in _Newline(lines))
f = tempfile.TemporaryFile()
for line in lines:
f.write(line)
f.seek(0)
lines = (l for l in f.readlines())
f.close()
lines = (l for l in _process(opts, lines))
for line in _replaceNewline(lines):
print line,
if __name__ == "__main__":
main()