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Set default value of an integer column SQLite

Posted by: admin November 29, 2017 Leave a comment

Questions:

I am creating an SQLite database in android.

db.execSQL("CREATE TABLE " + DATABASE_TABLE + " (" + KEY_ROWID
    + " INTEGER PRIMARY KEY AUTOINCREMENT, " + KEY_NAME
    + " TEXT NOT NULL, " + KEY_WORKED + " INTEGER, "
    + KEY_NOTE + " INTEGER);");

Is it possible to set the default value of KEY_NOTE (which is an integer) for every row created to be 0 (zero)? If so, what should be the correct code.

Answers:

Use the SQLite keyword default

db.execSQL("CREATE TABLE " + DATABASE_TABLE + " (" 
    + KEY_ROWID + " INTEGER PRIMARY KEY AUTOINCREMENT, "
    + KEY_NAME + " TEXT NOT NULL, "
    + KEY_WORKED + " INTEGER, "
    + KEY_NOTE + " INTEGER DEFAULT 0);");

This link is useful: http://www.sqlite.org/lang_createtable.html

Questions:
Answers:

A column with default value:

CREATE TABLE <TableName>(
...
<ColumnName> <Type> DEFAULT <DefaultValue>
...
)

<DefaultValue> is a placeholder for a:

  • value literal
  • ( expression )

Examples:

Count INTEGER DEFAULT 0,
LastSeen TEXT DEFAULT (datetime('now'))

Questions:
Answers:

It happens that I’m just starting to learn coding and I needed similar as you have just asked in SQLite (I´m using [SQLiteStudio] (3.1.1)).

It happens that you must define the column’s ‘Constraint‘ as ‘Not Null‘ then entering your desired definition using ‘Default‘ ‘Constraint‘ or it will not work (I don’t know if this is an SQLite or the program requirment).

Here is the code I used:

CREATE TABLE <MY_TABLE> (
<MY_TABLE_KEY>       INTEGER    UNIQUE
                                PRIMARY KEY,
<MY_TABLE_SERIAL>    TEXT       DEFAULT (<MY_VALUE>) 
                                NOT NULL
<THE_REST_COLUMNS>
);