SQLAlchemy原始SQL查詢NoSuchColumnError

Question

我有一個要使用sqlalchemy ORM執行的相對復雜的sql語句。 但是，當我嘗試這樣做時，總是會收到錯誤{NoSuchColumnError}"Could not locate column in row for column 'transaction_out.value'" 。 我的sql語句如下所示：

sql = """
Select
    addresses.address,
    transaction_out1.value As sent,
    transaction_out1.transaction_id As sent_id,
    transactions.block As block_sent,
    transactions.time As time_sent,
    transactions.txid As txid_sent,
    "sent" as type
From
    transaction_out INNER Join
    transaction_out_address On transaction_out_address.transaction_out_id = transaction_out.id INNER Join
    addresses On transaction_out_address.address_id = addresses.id INNER Join
    transaction_in On transaction_in.transaction_out_id = transaction_out.id INNER Join
    transactions On transaction_in.transaction_id = transactions.id INNER Join
    transaction_out transaction_out1 On transaction_out1.transaction_id = transactions.id INNER Join
    transactions transactions1 On transaction_out.transaction_id = transactions1.id
WHERE addresses.address=:address_string
UNION
Select
    addresses.address,
    transaction_out.value As received,
    transaction_out.transaction_id As received_id,
    transactions.block As received_block,
    transactions.time As received_time,
    transactions.txid As received_txid,
    "received"
From
    transaction_out LEFT Join
    transaction_out_address On transaction_out_address.transaction_out_id = transaction_out.id LEFT Join
    addresses On transaction_out_address.address_id = addresses.id LEFT Join
    transaction_in On transaction_in.transaction_out_id = transaction_out.id LEFT Join
    transactions On transaction_out.transaction_id = transactions.id
WHERE addresses.address=:address_string
"""

我嘗試通過以下方式執行該語句：

query = session.query(Address.address, TransactionOut.value, TransactionOut.id, Block.height, Transaction.time, Transaction.txid).from_statement(
        stmt.bindparams(
            bindparam("address_string",
            value=address_string)
))

我可以使用engine.execute()執行原始sql語句而不會出現任何問題，但是我需要使用session.query()來執行它，因此可以使用sqlalchemy-datatables。 我的數據庫或多或少類似於此處的數據庫： https : //dba.stackexchange.com/questions/137791/blockchain-bitcoin-as-a-database/137800#137800 。

我嘗試執行它的方式有什么問題？

Answer 1

原始SQL中的列別名將隱藏SQLAlchemy查詢中的列。 刪除它們，或更改查詢以適應它們：

query = session.query(Address.address,
                      TransactionOut.value.label('sent'),
                      TransactionOut.id.label('sent_id'),
                      Transaction.block.label('block_sent'),
                      Transaction.time.label('time_sent'),
                      Transaction.txid.label('txid_sent')).\
    from_statement(stmt).\
    params(address_string=address_string)