Search code examples
sqlstringsqlitevarchar

String - Varchar - SQLite datatypes

In SQLite, String - varchar can anyone tell the exact difference between both of this?

Solution

  • SQLite uses dynamic typing; the name of the declared data type does not matter:

    CREATE TABLE MyTable (
    Col1 TEXT,           -- this is stored as a text value
    Col2 STRING,         -- so is this
    Col3 VARCHAR(1),     -- and this
    Col4 FLUFFY BUNNIES, -- and this
    Col5,                -- and this
    Col6 INTEGER         -- and this, if the actual value is not a number
);

    The declared length is ignored, too (it's used only by the query planner to estimate the amount of I/O).

    To enforce data types or lengths, you would need a separate CHECK constraint:.

    CREATE TABLE MyTable (
    Col7 TEXT NOT NULL  CHECK(typeof(Col7) = 'text')
);