Options for beginning a new transaction.
Transactions can be created explicitly with calls to Datastore.BeginTransaction or implicitly by setting ReadOptions.new_transaction in read requests.
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{ // Union field |
| Fields | |
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Union field mode. The mode of the transaction, indicating whether write operations are supported. mode can be only one of the following: | |
readWrite |
The transaction should allow both reads and writes. |
readOnly |
The transaction should only allow reads. |
ReadWrite
Options specific to read / write transactions.
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{ "previousTransaction": string } |
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previousTransaction |
The transaction identifier of the transaction being retried. A base64-encoded string. |
ReadOnly
Options specific to read-only transactions.
| JSON representation |
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{ "readTime": string } |
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readTime |
Reads entities at the given time. This must be a microsecond precision timestamp within the past one hour, or if Point-in-Time Recovery is enabled, can additionally be a whole minute timestamp within the past 7 days. Uses RFC 3339, where generated output will always be Z-normalized and use 0, 3, 6 or 9 fractional digits. Offsets other than "Z" are also accepted. Examples: |