# RazorSQL

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# Informix Alter Table

The Informix Alter Table Tool allows users to visually alter tables. The Alter Table Tool can generate and/or execute the SQL that corresponds to any table alterations specified by the user.

The following options are available for the Informix Alter Table Tool.

Add Column - Adds a column to a table
Add Primary Key - Adds a primary key to a table
Add Foreign Key - Adds a foreign key to a table
Add Constraint - Adds a check constraint to a table
Change Column Type - Changes the data type of a column
Drop Column - Drops a column from a table
Drop Constraint - Drops a check constraint from a table

Listed below are some sample SQL statements generated by the Alter Table Tool.

ALTER TABLE sample:employee ADD newcol char(25) NOT NULL
ALTER TABLE sample:employee ADD CONSTRAINT PRIMARY KEY (ssn)
ALTER TABLE sample:employee
ADD CONSTRAINT FOREIGN KEY (dno)
REFERENCES sample:department(dnumber)