尝试对 PostgreSQL> 9.5 的值数组执行 UPSERT。
尝试像 SQLALchemy 文档中那样构建语句,但没有解释如何为数组而不是单行执行此操作。insert 语句正确构建,因此我想可以使用 on_conflict_do_update 函数执行此操作。
有这个代码:
stock_table = Table("stock_history", metadata,
Column('date', sqlalchemy.types.NVARCHAR(length=255), primary_key=True),
Column('product_id', sqlalchemy.types.INTEGER(), primary_key=True),
Column('product_sku', sqlalchemy.types.NVARCHAR(length=255)),
Column('on_hand_qty', sqlalchemy.dialects.postgresql.DOUBLE_PRECISION()),
Column('available_qty', sqlalchemy.dialects.postgresql.DOUBLE_PRECISION()),
Column('output_qty', sqlalchemy.dialects.postgresql.DOUBLE_PRECISION())
)
stock_today = pandas.read_sql_query(queryStock, odoo_engine)
insert_stmt = sqlalchemy.dialects.postgresql.insert(stock_table).values(stock_today)
upser_stmt = insert_stmt.on_conflict_do_update(
index_elements=['date', 'product_id'],
set_=stock_today.to_dict(orient='dict')
)
我收到以下错误:
属性错误:"StrSQLCompiler"对象没有属性"visit_on_conflict_do_update">
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
File "pompeiiETL.py", line 15, in <module>
pompeiiJobs.runStockJob(dwh_engine, odoo_prod_engine)
File "/Users/alex/Development/DataLab/pompeii-datalab/pompeiiETL/jobs.py", line 54, in runStockJob
print(upser_stmt)
File "/Users/alex/Development/DataLab/ETLenv/lib/python3.6/site-packages/sqlalchemy/sql/elements.py", line 446, in __str__
return str(self.compile())
File "<string>", line 1, in <lambda>
File "/Users/alex/Development/DataLab/ETLenv/lib/python3.6/site-packages/sqlalchemy/sql/elements.py", line 436, in compile
return self._compiler(dialect, bind=bind, **kw)
File "/Users/alex/Development/DataLab/ETLenv/lib/python3.6/site-packages/sqlalchemy/sql/elements.py", line 442, in _compiler
return dialect.statement_compiler(dialect, self, **kw)
File "/Users/alex/Development/DataLab/ETLenv/lib/python3.6/site-packages/sqlalchemy/sql/compiler.py", line 435, in __init__
Compiled.__init__(self, dialect, statement, **kwargs)
File "/Users/alex/Development/DataLab/ETLenv/lib/python3.6/site-packages/sqlalchemy/sql/compiler.py", line 216, in __init__
self.string = self.process(self.statement, **compile_kwargs)
File "/Users/alex/Development/DataLab/ETLenv/lib/python3.6/site-packages/sqlalchemy/sql/compiler.py", line 242, in process
return obj._compiler_dispatch(self, **kwargs)
File "/Users/alex/Development/DataLab/ETLenv/lib/python3.6/site-packages/sqlalchemy/sql/visitors.py", line 81, in _compiler_dispatch
return meth(self, **kw)
File "/Users/alex/Development/DataLab/ETLenv/lib/python3.6/site-packages/sqlalchemy/sql/compiler.py", line 2041, in visit_insert
insert_stmt._post_values_clause, **kw)
File "/Users/alex/Development/DataLab/ETLenv/lib/python3.6/site-packages/sqlalchemy/sql/compiler.py", line 242, in process
return obj._compiler_dispatch(self, **kwargs)
File "/Users/alex/Development/DataLab/ETLenv/lib/python3.6/site-packages/sqlalchemy/sql/visitors.py", line 79, in _compiler_dispatch
raise exc.UnsupportedCompilationError(visitor, cls)
sqlalchemy.exc.UnsupportedCompilationError: Compiler <sqlalchemy.sql.compiler.StrSQLCompiler object at 0x105b55be0> can't render element of type <class 'sqlalchemy.dialects.postgresql.dml.OnConflictDoUpdate'>
我错了什么?有没有更好的方法来进行更新?
谢谢!
Insert
如果我们写
db_uri = make_url('your-postgres-db-uri-here')
engine = create_engine(db_uri)
upser_stmt.bind = engine
print(upser_stmt)
它有效
我们还可以创建指定绑定的插入语句
insert_stmt = sqlalchemy.dialects.postgresql.insert(stock_table,
bind=engine).values(stock_today)
upser_stmt = insert_stmt.on_conflict_do_update(
index_elements=['date', 'product_id'],
set_=stock_today.to_dict(orient='dict')
)