in standard SQL, Oracle, and Mysql. True == 1 in standard SQL, False == 0. Both pgsql and Microsoft SQL server define a nonstandard boolean type that requires you to add a cast or an if statement, bulking up the query.
I did a shootout of mongodb and the three RDBMS systems (!Oracle) I mention for building a system to represent data from Freebase. It was possible to make a VARCHAR(4096) in mysql and only index the first 64 characters which meant I could map freebase types to mysql tables without running into index limitations -- I wanted the better GIS capabilities in pgsql, but I didn't want to double the size of my tables and queries to be able to handle strings losslessly.
select sum(x=1) from y;
in standard SQL, Oracle, and Mysql. True == 1 in standard SQL, False == 0. Both pgsql and Microsoft SQL server define a nonstandard boolean type that requires you to add a cast or an if statement, bulking up the query.
I did a shootout of mongodb and the three RDBMS systems (!Oracle) I mention for building a system to represent data from Freebase. It was possible to make a VARCHAR(4096) in mysql and only index the first 64 characters which meant I could map freebase types to mysql tables without running into index limitations -- I wanted the better GIS capabilities in pgsql, but I didn't want to double the size of my tables and queries to be able to handle strings losslessly.