4 ms·
Not quite right. The expression "CAST('321a' AS INTEGER)" will do as you suggest and ignore the trailing 'a' character, yielding an integer 123 result. But th
by SQLite 8y ago
Not quite right.
The expression "CAST('321a' AS INTEGER)" will do as you suggest and ignore the trailing 'a' character, yielding an integer 123 result. But that only happens for an explicit CAST. Automatic type conversions must be reversible. That means that '321a' is inserted as a string in an INTEGER column, but '321' (without the trailing 'a') will be converted into an integer 123.
PostgreSQL, MySQL, and SQL Server do exactly the same thing for the '321' case. For the '321a' case, the other three throw an error whereas SQLite just cancels the type conversion and inserts the original string.
- tonyarkles 8y agoAhhh cool! Either way, the fact that you can end up with strings in an Integer column is certainly surprising... sqlite> create table test (foo INTEGER); sqlite> insert into test (foo) values (123); sqlite> insert into test (foo) values ("blah"); sqlite> insert into test (foo) values ("123a"); sqlite> select * from test; 123 blah 123a
- hellofunk 8y agoIt’s not surprising if you read in the docs that it is an intended feature.