mysql转postgresql
使用步骤
-
使用mysqldump dump出PG兼容的MySQL建表语句（修改下面语句中的databasename和dumpfile.sql），此处dump语句很重要，一定要转为PG兼容的建表语句：
mysqldump --opt --compatible=postgresql --default-character-set=utf8 -d databasename -r dumpfile.sql -u username -p -
执行转换脚本，dumpfile.sql和adbforpg.sql填写真实的值
python db_converter.py dumpfile.sql adbforpg.sql
adbforpg.sql是转换后的ADB for PG的建表语句，如果需要有需改需求，可以直接在文件中进行修改。重点要关注一下分布列的选择，默认选择MySQL表中的主键作为分布列，如果MySQL表结构中无主键，请手动修改选择分布列。
# encoding=utf8
# !/usr/bin/env python
"""
Fixes a MySQL dump made with the right format so it can be directly
imported to a new PostgreSQL database.
Dump using:
mysqldump --opt --compatible=postgresql --default-character-set=utf8 -d databasename -r dumpfile.sql -u root -p
"""
import re
import sys
import os
import time
import subprocess
reload(sys)
sys.setdefaultencoding('utf8')
def parse(input_filename, output_filename):
"Feed it a file, and it'll output a fixed one"
# State storage
if input_filename == "-":
num_lines = -1
else:
num_lines = int(subprocess.check_output(["wc", "-l", input_filename]).strip().split()[0])
tables = {}
current_table = None
creation_lines = []
cast_lines = []
index_lines = []
comment_line = []
num_inserts = 0
started = time.time()
primary_key = None
# Open output file and write header. Logging file handle will be stdout
# unless we're writing output to stdout, in which case NO PROGRESS FOR YOU.
if output_filename == "-":
output = sys.stdout
logging = open(os.devnull, "w")
else:
output = open(output_filename, "w")
logging = sys.stdout
if input_filename == "-":
input_fh = sys.stdin
else:
input_fh = open(input_filename)
output.write("-- Converted by db_converter\n")
output.write("START TRANSACTION;\n")
# output.write("SET standard_conforming_strings=off;\n")
# output.write("SET escape_string_warning=off;\n")
# output.write("SET CONSTRAINTS ALL DEFERRED;\n\n")
for i, line in enumerate(input_fh):
time_taken = time.time() - started
percentage_done = (i + 1) / float(num_lines)
secs_left = (time_taken / percentage_done) - time_taken
logging.write("\rLine %i (of %s: %.2f%%) [%s tables] [%s inserts] [ETA: %i min %i sec]" % (
i + 1,
num_lines,
((i + 1) / float(num_lines)) * 100,
len(tables),
num_inserts,
secs_left // 60,
secs_left % 60,
))
logging.flush()
line = line.decode("utf8").strip().replace(r"\\", "WUBWUBREALSLASHWUB").replace(r"\'", "''").replace("WUBWUBREALSLASHWUB", r"\\")
# Ignore comment lines
if line.startswith("--") or line.startswith("/*") or line.startswith("LOCK TABLES") or line.startswith("DROP TABLE") or line.startswith("UNLOCK TABLES") or not line:
continue
# Outside of anything handling
if current_table is None:
# Start of a table creation statement?
if line.startswith("CREATE TABLE"):
current_table = line.split('"')[1].lower()
tables[current_table] = {"columns": []}
creation_lines = []
else:
print "\n ! Unknown line in main body: %s" % line
# Inside-create-statement handling
else:
# Is it a column?
if line.startswith('"'):
useless, name, definition = line.strip(",").split('"', 2)
name = name.lower()
try:
type, extra = definition.strip().split(" ", 1)
except ValueError:
type = definition.strip()
extra = ""
extra = re.sub("CHARACTER SET [\w\d]+\s*", "", extra)
extra = re.sub("COLLATE [\w\d]+\s*", "", extra.replace("'0000-00-00 00:00:00'", "NULL"))
if extra.find("COMMENT '") > -1:
pattern = re.compile("COMMENT '(.*)'")
comment_line.append(u"COMMENT ON COLUMN \"%s\".\"%s\" is '%s'" % (current_table, name, pattern.findall(extra)[0]))
extra = re.sub("COMMENT '.*'", "", extra)
# See if it needs type conversion
final_type = None
if type.startswith("tinyint("):
type = "smallint"
elif type.startswith("int(") and extra.startswith("unsigned"):
type = "bigint"
elif type.startswith("int("):
type = "integer"
elif type.startswith("smallint(") and extra.startswith("unsigned"):
type = "integer"
elif type.startswith("smallint("):
type = "smallint"
elif type.startswith("mediumint("):
type = "integer"
elif type.startswith("bigint("):
type = "bigint"
elif type.startswith("year"):
type = "integer"
elif type == "longtext":
type = "text"
elif type == "mediumtext":
type = "text"
elif type == "tinytext":
type = "text"
elif type.startswith("varchar("):
size = int(type.split("(")[1].split(")")[0])
type = "varchar(%s)" % (size * 2)
elif type == "datetime":
type = "timestamp without time zone"
elif type == "timestamp":
type = "timestamp with time zone"
elif type == "double":
type = "double precision"
elif type.startswith("float"):
type = "real"
elif type.endswith("blob"):
type = "bytea"
elif type.endswith("binary"):
type = "bytea"
elif type.startswith("enum(") or type.startswith("set("):
type = "varchar"
elif type.startswith("linestring"):
type = "path"
elif type.startswith("point"):
type = "point"
extra = extra.replace("unsigned", "")
if final_type:
cast_lines.append(
"ALTER TABLE \"%s\" ALTER COLUMN \"%s\" DROP DEFAULT, ALTER COLUMN \"%s\" TYPE %s USING CAST(\"%s\" as %s)" % (current_table, name, name, final_type, name, final_type))
creation_lines.append('"%s" %s %s' % (name, type, extra))
tables[current_table]['columns'].append((name, type, extra))
# Is it a constraint or something?
elif line.startswith("PRIMARY KEY"):
creation_lines.append(line.rstrip(",").lower())
primary_key = line.split("(")[1].split(")")[0].lower()
elif line.startswith("UNIQUE KEY"):
creation_lines.append("UNIQUE (%s)" % line.split("(")[1].split(")")[0].lower())
elif line.startswith("KEY"):
index_lines.append("CREATE INDEX %s on \"%s\" (%s)" % (line.split(" ")[1], current_table, line.split("(")[1].split(")")[0].lower()))
# Is it the end of the table?
elif line == ");" or line == ")":
output.write("CREATE TABLE \"%s\" (\n" % current_table)
for i, line in enumerate(creation_lines):
output.write(" %s%s\n" % (line, "," if i != (len(creation_lines) - 1) else ""))
if primary_key is not None:
output.write(') distributed by (%s);\n\n' % primary_key)
else:
output.write(') distributed by ();\n\n')
current_table = None
primary_key = None
# ???
else:
print "\n ! Unknown line inside table creation: %s" % line
# Finish file
output.write("\n-- Post-data save --\n")
output.write("\n-- Add Comment --\n")
for line in comment_line:
output.write(u"%s;\n" % line)
output.write("COMMIT;\n\n")
# Write index out
# output.write("START TRANSACTION;\n")
# output.write("\n-- Index --\n")
# for line in index_lines:
# output.write("%s;\n" % line)
#
# # Finish file
# output.write("\n")
# output.write("COMMIT;\n")
print ""
if __name__ == "__main__":
parse(sys.argv[1], sys.argv[2])
参考:https://github.com/wuchase/mysql-postgresql-converter