The expression can't be a subquery or contain alias data types.Ĭomputed columns can be used in select lists, WHERE clauses, ORDER BY clauses, or any other locations in which regular expressions can be used, with the following exceptions:Ĭomputed columns must be marked PERSISTED to participate in a FOREIGN KEY or CHECK constraint.Ī computed column can be used as a key column in an index or as part of any PRIMARY KEY or UNIQUE constraint, if the computed column value is defined by a deterministic expression and the data type of the result is allowed in index columns.įor example, if the table has integer columns a and b, the computed column a + b may be indexed, but computed column a + DATEPART(dd, GETDATE()) can't be indexed because the value may change in subsequent invocations. The expression can be a noncomputed column name, constant, function, variable, and any combination of these connected by one or more operators. For example, a computed column can have the definition: cost AS price * qty. The column is computed from an expression that uses other columns in the same table. A computed column is a virtual column that isn't physically stored in the table, unless the column is marked PERSISTED. column_name AS computed_column_expressionĪn expression that defines the value of a computed column. You don't specify columns because a FileTable has a fixed schema. AS FileTableĪpplies to: SQL Server 2012 (11.x) and later.Ĭreates the new table as a FileTable. table_name can be a maximum of 128 characters, except for local temporary table names (names prefixed with a single number sign ( #)) that can't exceed 116 characters. Table names must follow the rules for identifiers. The name of the schema to which the new table belongs. The login for the current connection must be associated with an existing user ID in the database specified by database_name, and that user ID must have CREATE TABLE permissions. If not specified, database_name defaults to the current database. User-friendly interface for data science. database_name must specify the name of an existing database. SQL OnLine - Next gen SQL Editor: SQLite, MariaDB / MySQL, PostgreSQL, MS SQL Server. The name of the database in which the table is created. To view Transact-SQL syntax for SQL Server 2014 and earlier, see Previous versions documentation. Simple CREATE TABLE syntax (common if not using options): CREATE TABLE Transact-SQL syntax conventions Syntax options Common syntax For Azure Synapse Analytics syntax, see CREATE TABLE (Azure Synapse Analytics).
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