Han*_*nny 1 python django django-models
我在django(非常小的项目)中设置了我的迁移; 但是我有一个.sql文件,它在数据库中有一堆我需要的数据.
在运行迁移之后/期间执行此.sql文件的最佳方式(或者甚至可能)是什么?
sql文件只包含数据的插入,如下所示:
INSERT INTO `mileages_mileages` (`id`, `miles`, `start_location`, `end_location`) VALUES
(NULL,3, 'Location 1', 'Location 2'),
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我只需要在运行模型的初始迁移后执行该.sql文件.
那可能吗?
migrations.RunSQL()
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不接受文件作为输入.只有原始SQL.要解决这个问题,您需要使用:
migrations.RunSQL(
"""
INSERT INTO 'mileages_mileages' ('id', 'miles', 'start_location', 'end_location')
VALUES
(NULL,3, 'Location 1', 'Location 2');
""")
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要么
def load_data_from_sql(apps, schema_editor):
file_path = os.path.join(os.path.dirname(__file__), 'file_name.sql')
sql_statement = open(file_path).read()
with connection.cursor() as c:
c.execute(sql_statement)
class Migration(migrations.Migration):
dependencies = [
('..', '...'),
]
operations = [
migrations.RunPython(load_data_from_sql),
]
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这是完整的脚本(不完美,但原样),用于将带有 DELIMITER 的 MySQL 语句转换为 SQL 执行。
有关 SQL 语句中的乘法分隔符的信息/sf/answers/3660488331/
有两个使用脚本的示例:运行 sql 文件或运行原始 MySQL 语句
from anywhere import migrate_run_sql
operations = [
migrations.RunPython(migrate_run_sql.run_sql_file('contract_triggers.sql')),
migrations.RunPython(migrate_run_sql.run_sql(
"""
DELIMITER $$
CREATE TRIGGER trigger_name BEFORE INSERT ON table
FOR EACH ROW
BEGIN
IF NEW.number <> 'anynumber' AND NEW.number <> 'anynumber'
THEN
SET NEW.number = 'anynumber';
END IF;
END$$
"""
))
]
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# -*- coding: utf-8 -*-
from django.db import connection
import re
from StringIO import StringIO
from django.conf import settings
import os
# this function get raw MySQL statement
def run_sql(sql):
def load_data_from_sql(app, schema_editor):
f = StringIO(sql)
return _runsql(f)
return load_data_from_sql
# this function get sql file
def run_sql_file(filename):
def load_data_from_sql(app, schema_editor):
filepath = os.path.join(settings.PROJECT_PATH, '../deploy/mysql/', filename)
with open(filepath, 'rb') as f:
return _runsql(f)
return load_data_from_sql
# in this function content splits and checks line by line
def _runsql(f):
with connection.cursor() as c:
file_data = f.readlines()
statement = ''
delimiter = ';\n'
for line in file_data:
if re.findall('DELIMITER', line): # found delimiter
if re.findall('^\s*DELIMITER\s+(\S+)\s*$', line):
delimiter = re.findall('^\s*DELIMITER\s+(\S+)\s*$', line)[0] + '\n'
continue
else:
raise SyntaxError('Your usage of DELIMITER is not correct, go and fix it!')
statement += line # add lines while not met lines with current delimiter
if line.endswith(delimiter):
if delimiter != ';\n':
statement = statement.replace(';', '; --').replace(delimiter, ';') # found delimiter, add dash symbols (or any symbols you want) for converting MySQL statements with multiply delimiters in SQL statement
c.execute(statement) # execute current statement
statement = '' # begin collect next statement
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希望它会有所帮助!
阅读更多内容后,运行 SQL 来加载迁移中的数据是错误的方法。使用固定装置要好得多。
此后我添加了一个固定装置并将使用该文件来引入数据。
首先,要创建固定装置,我必须将数据添加到表中(我只是手动运行 SQL 文件以将其添加到相应的表中)。
然后我跑了
manage.py dumpdata mileage.mileage --indent 2 --format=json --output initial_mileages.json
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这创建了我的装置,然后我加载了它
manage.py loaddata initial_mileages.json
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而且导入得很漂亮。