Instead, Boolean values are stored as integers 0 (false) and 1 the flip side, SQLite supports datetimes, despite not being one of those five types, so this answer is inconclusive" Instead, Boolean values are stored as integers 0 (false) and 1 (true). SQLite does not have a separate Boolean storage class. Boolean Datatype SQLite does not have a separate Boolean storage class. NONE A column with affinity NONE does not prefer one storage class over another and no attempt is made toĬoerce data from one storage class into another.REAL Behaves like a column with NUMERIC affinity except that it forces integer values into floating point representation.INTEGER Behaves the same as a column with NUMERIC affinity.NUMERIC This column may contain values using all five storage.TEXT This column stores all data using storage classes NULL, TEXT or.Each table column in an SQLite3 database is assigned one of the following type affinities: Any column can still store any type of data but the preferred storage class for a column is called its affinity. SQLite supports the concept of type affinity on columns. When a columns value is compared with the result of an expression (e.g. You can create column of BOOLEAN type using standard CREATE TABLE . Note, SQLite does not have a Boolean datatype, instead 1 is used to indicate. TEXT that looks like a number (eg "0", "1", "5"): Behaves like NUMERIC, listed above. Actually, SQLite does support BOOLEAN type, but may be not exactly in the way you expect.Even values like "t", "TRUE", "true", "True" still match IS FALSE The SQLite CASE expression evaluates a list of conditions and returns an expression based on the result of the evaluation. Any TEXT that does not parse to a numeric value: IS FALSE.Any zero NUMERIC, INTEGER, or REAL: IS FALSE.Any non-zero NUMERIC, INTEGER, or REAL: IS TRUE.
In most cases, youre writing an expression. For instance, where expects an expression that returns a boolean. SELECT * FROM blah WHERE some_column IS TRUE Īnd it will work how you expect if you are using 0 for false and 1 for true.įrom my testing, here is how SQLite matches various values: Expressions are used in all kinds of situations. SELECT * FROM blah WHERE some_column IS FALSE If a null value affects the result of a logical expression, the result is neither true nor false but unknown. SQL’s three valued logic is a consequence of supporting null to mark absent data. However, this is completely independent of whether SQLite supports boolean literals and comprehensions.įor anyone wondering, the answer is YES, since SQLite 3.23 you can do boolean comprehensions with the boolean literals TRUE and FALSE, and it will work how you expect. The Three-Valued Logic of SQL true unknown false SQL uses a three-valued logic: besides true and false, the result of logical expressions can also be unknown. As everyone else has pointed out, SQLite does not support a specific boolean storage type, and the OP specifically acknowledges this fact.
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