One method to alter a column definition is to use a MODIFY clause. The name of the column to be changed must be specified, followed by its new definition. Assume that the ID column's data type must be changed from INT to BIGINT, to allow the table to accommodate larger identification numbers. In addition, the column needs to be changed to UNSIGNED to disallow negative values. The following statement accomplishes this task: ALTER TABLE eu_countries MODIFY new_population BIGINT(12) NOT NULL; That ALTER TABLE statement changes the table structure as follows: +----------------------+-------------------+-------+------+----------+--------+ | Field | Type | Null | Key | Default | Extra | +----------------------+-------------------+-------+------+----------+...
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