영어에서 Computed column 을 사용하는 예와 한국어로 번역
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Colloquial
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Ecclesiastic
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Ecclesiastic
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Programming
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Computer
Shows the formula for a computed column.
A mask cannot be configured on a computed column, butif the computed column depends on a column with a MASK, then the computed column will return masked data.
This column is blank for computed columns.
As with key columns, computed columns derived from image, ntext, and text data types can be nonkey(included) columns as long as the computed column data type is allowed as a nonkey index column. .
Indexes with Computed Columns.
A 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. .
Index on computed column.
You can expose values from JSON column as computed columns.
Index on computed columns.
SET ANSI_WARNINGS must be ON when you are creating or manipulating indexes on computed columns or indexed views.
For example, if the table has integer columns a and b, the computed column a+ b can be indexed, but computed column a+ DATEPART(dd, GETDATE()) cannot be indexed because the value may change in subsequent invocations.
Consider creating index on computed columns.
For example, if the table has integer columns a and b, the computed column a+ b can be indexed, but computed column a+ DATEPART(dd, GETDATE()) cannot be indexed because the value may change in subsequent invocations.
As part of the SEEK predicate, the partitions to be accessed are identified by a range predicate on the computed column representing the partition ID.
A 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. .
These functions are sometimes not deterministic, but may be used in indexed views or indexes on computed columns when they're specified in a deterministic way.
In the past, this type of key had to be maintained by hand but nowadays you can use a computed column as part or all of any primary key or unique constraint, as long as the computed column value is defined by a deterministic expression and the data type of the result is allowed in index columns. .
In the past, this type of key had to be maintained by hand but nowadays you can use a computed column as part or all of any primary key or unique constraint, as long as the computed column value is defined by a deterministic expression and the data type of the result is allowed in index columns. .
For example, computing a Column Pattern profile for a column that contains numeric or datetime values is not meaningful.