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Reviewed-by: Pruthi, Vineet <vineet.pruthi@t-systems.com> Co-authored-by: Su, Xiaomeng <suxiaomeng1@huawei.com> Co-committed-by: Su, Xiaomeng <suxiaomeng1@huawei.com>
4.5 KiB
4.5 KiB
AS for Column
Function
This statement is used to specify an alias for a column.
Syntax
1 | SELECT attr_expr [AS] alias, attr_expr [AS] alias, ... FROM table_reference; |
Keyword
- alias: gives an alias for the attr_expr field.
- AS: Whether to add AS does not affect the result.
Precautions
- The to-be-queried table must exist. Otherwise, an error is reported.
- The alias must be specified before execution of the statement. Otherwise, an error is reported. You are advised to specify a unique alias.
Example
Run SELECT name AS n FROM simple_table WHERE score > 90 to obtain the subquery result. The alias n for name can be used by external SELECT statement.
1 | SELECT n FROM (SELECT name AS n FROM simple_table WHERE score > 90) m WHERE n = "xiaoming"; |
Parent topic: Alias