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I've found it very weird that simple code like this is not valid:
select * from table where field=true
The alternative apparently being
select * from table where field='true'
Ok, guess I can live with that. For one reason or another I needed to do something like this recently:
select true as somefield,...
The alternative to get types and everything right was much more ugly though:
select cast('true' as bit) as somefield,...
Am I missing something? Is there actually some built in way to get a true or false value as a boolean without casting?
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Both CAST and CONVERT are functions used to convert one data type to another data type. It is mainly used in the Microsoft SQL program, and both are often used interchangeably.
You can insert a boolean value using the INSERT statement: INSERT INTO testbool (sometext, is_checked) VALUES ('a', TRUE); INSERT INTO testbool (sometext, is_checked) VALUES ('b', FALSE); When you select a boolean value, it is displayed as either 't' or 'f'.
In SQL you use 0 and 1 to set a bit field (just as a yes/no field in Access). In Management Studio it displays as a false/true value (at least in recent versions). When accessing the database through ASP.NET it will expose the field as a boolean value.
There is boolean data type in SQL Server. Its values can be TRUE , FALSE or UNKNOWN . However, the boolean data type is only the result of a boolean expression containing some combination of comparison operators (e.g. = , <> , < , >= ) or logical operators (e.g. AND , OR , IN , EXISTS ).
Bits are the datatype most commonly used to represent a boolean in T-SQL. I typically do something like this:
select CAST(1 as bit) as somefield
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