sqlite 字符串拼接

select path || '%'  from t_category where depth = 0 and type = 0

用'||'拼接字符串

比如path是/1001/的話 那結果就是/1001/%

 

數字相加

SELECT 'A'+'B'  結果為0

SELECT "A"+"1"  結果為1

SELECT "A"+1   結果為1

SELECT 2+1  結果為3

=在“+”運算中，SQLite將字符串非數字串都當作0處理了

 

||  String Concatenation
*  Arithmetic Multiply
/  Arithmetic Divide
%  Arithmetic Modulus
+  Arithmetic Add
–  Arithmetic Subtract
<<  Bitwise Right shift
>>  Bitwise Left shift
&  Logical And
|  Logical Or
<  Relational Less than
<=  Relational Less than or equal to
>  Relational Greater than
>=  Relational Greater than or equal to
=  Relational Equal to
==  Relational Equal to
<>  Relational Not equal to
!=  Relational Not equal to
IN  Logical In
AND  Logical And
OR  Logical Or
LIKE  Relational String matching
GLOB  Relational Filename matching