feat: implement the concat macro

README.md

@@ -59,8 +59,9 @@ This dbt package contains macros for SQL functions to run the dbt project on mul
   - [test_unique_combination_of_columns](#test_unique_combination_of_columns-source)
   - [test_unique](#test_unique-source)
 - [Generic](#Generic)
-  - [optional](#optional-source)
+  - [concat](#concat-source)
   - [left_from_char](#left_from_char-source)
+  - [optional](#optional-source)
 - [Process mining tables](#Process-mining-tables)
   - [generate_edge_table](#generate_edge_table-source)
   - [generate_variant](#generate_variant-source)
@@ -402,6 +403,15 @@ models:
 
 ### Generic
 
+#### concat ([source](macros/generic/concat.sql))
+This macro concatenates two or more strings together. In case a value is `null` it is concatenated as the empty string `''`. 
+
+Usage: 
+`{{ pm_utils.concat('"Field_A"', '"Field_B"') }}`
+
+To pass a string as argument, make sure to use double quotes:
+`{{ pm_utils.concat('"Field_A"', "' - '", '"Field_B"') }}`
+
 #### left_from_char ([source](macros/generic/left_from_char.sql))
 This macro extracts the string left from the character.
 

macros/generic/concat.sql

@@ -0,0 +1,12 @@
+{%- macro concat() -%}
+
+concat(
+{%- for argument in varargs -%}
+    coalesce({{ argument }}, '')
+    {%- if not loop.last -%}
+        ,
+    {%- endif -%}
+{%- endfor -%}
+)
+
+{%- endmacro -%}