concat function¶
The concat()
and concat_ws()
functions return strings concatenated by one or more strings.
concat() function¶
The concat()
function requires at least two or more strings. All the parameters are concatenated into one string.
- If there is only one string, the string itself is returned.
- If any one of the strings is
NULL
,NULL
is returned.
Syntax¶
concat(string1,string2,...)
Examples¶
//This example concatenates 1, 2, and 3.
nebula> RETURN concat("1","2","3") AS r;
+-------+
| r |
+-------+
| "123" |
+-------+
//In this example, one of the string is NULL.
nebula> RETURN concat("1","2",NULL) AS r;
+----------+
| r |
+----------+
| __NULL__ |
+----------+
nebula> GO FROM "player100" over follow \
YIELD concat(src(edge), properties($^).age, properties($$).name, properties(edge).degree) AS A;
+------------------------------+
| A |
+------------------------------+
| "player10042Tony Parker95" |
| "player10042Manu Ginobili95" |
+------------------------------+
concat_ws() function¶
The concat_ws()
function connects two or more strings with a predefined separator.
- If the separator is
NULL
, theconcat_ws()
function returnsNULL
.
- If the separator is not
NULL
and there is only one string, the string itself is returned.
- If the separator is not
NULL
and there is aNULL
in the strings,NULL
is ignored during the concatenation.
Syntax¶
concat_ws(separator,string1,string2,... )
Examples¶
//This example concatenates a, b, and c with the separator +.
nebula> RETURN concat_ws("+","a","b","c") AS r;
+---------+
| r |
+---------+
| "a+b+c" |
+---------+
//In this example, the separator is NULL.
neubla> RETURN concat_ws(NULL,"a","b","c") AS r;
+----------+
| r |
+----------+
| __NULL__ |
+----------+
//In this example, the separator is + and there is a NULL in the strings.
nebula> RETURN concat_ws("+","a",NULL,"b","c") AS r;
+---------+
| r |
+---------+
| "a+b+c" |
+---------+
//In this example, the separator is + and there is only one string.
nebula> RETURN concat_ws("+","a") AS r;
+-----+
| r |
+-----+
| "a" |
+-----+
nebula> GO FROM "player100" over follow \
YIELD concat_ws(" ",src(edge), properties($^).age, properties($$).name, properties(edge).degree) AS A;
+---------------------------------+
| A |
+---------------------------------+
| "player100 42 Tony Parker 95" |
| "player100 42 Manu Ginobili 95" |
+---------------------------------+
Last update:
January 14, 2022