When ALWAYS is used, you cannot provide your own values for the identity column. If the automatically assigned values are beyond the range of the identity column type, the query will fail. Both parameters are optional, and the default value is 1. Assigned values are unique but are not guaranteed to be contiguous. The automatically assigned values start with start and increment by step. This clause can only be used for columns with BIGINT data type. This clause is only supported for Delta Lake tables. When you write to the table, and do not provide values for the identity column, it will be automatically assigned a unique and statistically increasing (or decreasing if step is negative) value. GENERATED AS IDENTITY ) ]Īpplies to: Databricks SQL Databricks Runtime 10.3 and aboveĭefines an identity column. When you specify this clause the value of this column is determined by the specified expr.Įxpr may be composed of literals, column identifiers within the table, and deterministic, built-in SQL functions or operators except: If specified the column will not accept NULL values. Not all data types supported by Databricks are supported by all data sources. If you do not define columns the table schema you must specify either AS query or LOCATION. This optional clause defines the list of columns, their types, properties, descriptions, and column constraints. If the name is not qualified the table is created in the current schema. The name must not include a temporal specification. IF NOT EXISTS cannot coexist with REPLACE, which means CREATE OR REPLACE TABLE IF NOT EXISTS is not allowed. If specified and a table with the same name already exists, the statement is ignored. When an external table is dropped the files at the LOCATION will not be dropped. When creating an external table you must also provide a LOCATION clause. INSERT OVERWRITE DIRECTORY with Hive formatĭatabricks strongly recommends using REPLACE instead of dropping and re-creating Delta Lake tables.Federated queries (Lakehouse Federation).Privileges and securable objects in the Hive metastore.Privileges and securable objects in Unity Catalog.
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