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2 Μαρ 2016 · You can't dictate the data type for the output column of a view. The best you can do is as @buckley suggested - use CAST or CONVERT to force an explicit data type inline in the view definition. – Aaron Bertrand
This chapter teaches you the following: How to create and modify tables. The types of tables available in SQL Server. The advantages and usage of views. How to use extended properties to store metadata (information that describes objects) in a database. Creating and Altering Tables.
To change the data type of a column in a table, use the following syntax: SQL Server / MS Access: ALTER TABLE table_name. ALTER COLUMN column_name datatype; My SQL / Oracle (prior version 10G): ALTER TABLE table_name. MODIFY COLUMN column_name datatype; Oracle 10G and later: ALTER TABLE table_name.
Chapter 5 Outline. More Complex SQL Retrieval Queries. Specifying Constraints as Assertions and Actions as Triggers. Views (Virtual Tables) in SQL. Schema Change Statements in SQL.
The SELECT statement following the AS keyword defines the new query that will be used to redefine the view. You can change the columns selected, add new conditions, or modify any other part of the original query. Let’s look at some common use cases for the ALTER VIEW statement: 1. Adding or Removing Columns.
SQL Server allows you to perform the following changes to an existing column of a table: Modify the data type. Change the size. Add a NOT NULL constraint. Modify column’s data type. To modify the data type of a column, you use the following statement: ALTER TABLE table_name . ALTER COLUMN column_name new_data_type(size);
Simple row-level triggers are easier to implement. Statement-level triggers require significant amount of state to be maintained in OLD TABLE and NEW TABLE. However, a row-level trigger gets fired for each row, so complex row-level triggers may be inefficient for statements that modify many rows.
