Altering SQLite column type and adding PK constraint

Question

How to change the type of a column in a SQLite table?

I\'ve got:

    CREATE TABLE table(
        id INTEGER,
        salt TEXT NOT NULL UNIQUE,
        s         


        

Answer 1

Since RDBMS is not specified, these are DB2 queries:

1. Make ID as primary key:

   ALTER TABLE table
       ADD CONSTRAINT pk_id
       PRIMARY KEY (id)

2. Make salt as not UNIQUE:

   ALTER TABLE table
       DROP UNIQUE 

3. Make salt nullable:

   ALTER TABLE table
       ALTER COLUMN salt DROP NOT NULL

You will need to do a reorg after drop not null. This is to be done from the command prompt.

reorg table