Specifies the dataset used to resolve unqualified table references in SQL queries.

データ型

string

デフォルト値

""

解説

When a query references a table without specifying a dataset, this property determines how the 本製品 resolves the dataset. Using a defined DatasetId can reduce ambiguity and improve reliability in query parsing, particularly in passthrough scenarios.

Tables in Google BigQuery can be referenced either with or without a dataset:

/* Unqualified reference (dataset resolved from connection) */
SELECT FirstName, LastName FROM `customers`

/* Fully qualified reference */
SELECT FirstName, LastName FROM `project-id`.`Northwind`.`customers`

The 本製品 uses the following rules to resolve unqualified tables:

1. If DatasetId is set, its value is used as the default dataset.
2. If not set, the dataset of the first fully qualified table in the query is used to resolve any unqualified tables.

For example, in the following query, orders is treated as part of the Northwind dataset:

SELECT * FROM `project-id`.`Northwind`.`customers`
INNER JOIN `orders` ON ...

When QueryPassthrough is enabled, only the first rule applies. In passthrough mode, either set this property or qualify all table names explicitly.

Set this property when working with queries that include unqualified table names, especially if you're using passthrough or querying across multiple datasets.