![]() ![]() Learn how to use Beekeeper Studio with bite-sized articles. See a list of everything Beekeeper Studio has to offer Work across multiple devices, or share your connections and queries with others. Quickly iterate on a SQL query, view and visualize results, and share with a colleague.Ī spreadsheet like interface to view, navigate, search, and edit your data.Īn easy to use no-code interface to create and alter tables, indexes, foreign keys, and more. But that's what it means.Boolean Columns in SQLite: A Beginner’s Guide | Beekeeper Studio Beekeeper Studio menuĮxperience a truly modern SQL editor that really sweats the details. Forced by the syntax to provide a one-word answer, it couldn't (more honestly) say missing integer. What TYPEOF is really saying is that the output of CAST in this case, when combined with something else, will be treated as NULL. But there is not the missing value has no type. (You cannot, for example, CAST(REAL as TEXT) because "REAL" is a type, and CAST wants a value.) The output of TYPEOF is a type, or would be, if type there was. The first parameter to CAST is a value because values may be missing, CAST accepts NULL in place of a value. ![]() SQLite's output here is shorthand, the product of inexpressibility. But nullity trumps all: sqlite> select typeof(cast(NULL as int)) as hello That's why columns are declared with a type and NULL or NOT NULL: two distinct attributes of the attribute. It's a property of a place where a value would otherwise be. It's definitely not a value, despite the common use of "NULL value". Hmm, is NULL a type? It's a value in a ternary logic system. It has NULL, BLOB, TEXT, INTEGER, and REAL A text constant is never equal to an integer constant. However testing whether something equals 1 or 0 does not require any conversions whatsoever unless the affinity conversion rules apply. If you want to know if something IS TRUE or IS FALSE then it must be converted to numeric first - you have no choice in the matter. Something which evaluates to a non-zero and non-null numeric value IS TRUE, and something which evaluates to a zero value IS FALSE. TRUE and FALSE are "magical words" unless there is a column in one of the tables in the query named TRUE or FALSE, in which case it is that column and not the magical value. It has NULL, BLOB, TEXT, INTEGER, and REAL (INTEGER and REAL can be called NUMERIC, which is a Schrodinger's type - you don't know if it is INTEGER or REAL until after you have looked in the box).įor the purpose of comparison (greater than, less than, equals, not equals) or assignment, then TRUE is the INTEGER 1 and FALSE is the INTEGER 0.įor the purpose of IS (a test of being), IS TRUE means "not null and not zero" and IS FALSE means "not null and one of 0, 0.0 or -0.0". If it is not comparing the value, is it comparing the type? But because the result is always false, I couldn't tell whether I get a correct result. Similarly, what is the meaning of = in '1xxx'=TRUE is not explained. In the case of my examples, if it is meaningless to compare a string with a Boolean, it should raise a warning or forbid the user from using the comparison, which leads to never true result. Vice versa, it could also convert the right hand side to a string and compare. If I do select '1xxx'=TRUE, it is intuitively expected to convert the left hand side to a bool. Intuitively, when comparing with =, the engine should do the conversion itself. I expected it should implicitly convert the string to a number/Boolean when I compare it to a number/Boolean. Secondly, it doesn't explain why '1english' is neither a FASLE or a TRUE. I think it could be adjusted to state the string must start with a number to be evaluated to true. It only gives the example which starts with a number. First, for the documentation, it doesn't explicitly state the string should start with a number.
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