> For the complete documentation index, see [llms.txt](https://upsolver.gitbook.io/content/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://upsolver.gitbook.io/content/reference-1/functions-and-operators/functions/string/join_arrays.md).

# JOIN\_ARRAYS

Joins any number of arrays by index using a MessageFormat pattern.

## Syntax

```sql
JOIN_ARRAYS(formatString, inputs1[, inputs2, ..., inputsN])
```

## Arguments

<table><thead><tr><th>Name</th><th width="153">Type</th><th width="238">Description</th><th>Default Value</th></tr></thead><tbody><tr><td>formatString</td><td>string</td><td>The format string where {n} prints the n'th input. For example, the pattern '{0}.{0}.{1}' on the inputs 'a' and 'b' will result in the string 'a.a.b'</td><td>null</td></tr><tr><td>inputs#</td><td>any</td><td></td><td></td></tr></tbody></table>

## Returns

Returns a `string` value.

***

## Examples

<table><thead><tr><th>formatString</th><th>inputs1</th><th width="172">inputs2</th><th>inputs3</th><th>Output</th></tr></thead><tbody><tr><td>'{0} {1} is {2} years old'</td><td>array['John', 'Jane']</td><td>array['Smith', 'Johnson']</td><td>array[35, 32]</td><td>[<code>John Smith is 35 years old</code>, <code>Jane Johnson is 32 years old</code>]</td></tr><tr><td>'{0}:{1}'</td><td>array['red', 'green', 'blue', 'luminosity']</td><td>array[255, 255, 0]</td><td></td><td>[<code>red:255</code>, <code>green:255</code>, <code>blue:0</code>, <code>luminosity:</code>]</td></tr></tbody></table>

### Transformation job example

#### SQL

```sql
CREATE JOB function_operator_example
    ADD_MISSING_COLUMNS = true
AS INSERT INTO default_glue_catalog.upsolver_samples.orders_transformed_data 
 MAP_COLUMNS_BY_NAME
  SELECT formatString, inputs1[], inputs2[], inputs3[],
  JOIN_ARRAYS('{0} {1} is {2} years old', inputs1[], inputs2[], inputs3[]) AS Output
  FROM default_glue_catalog.upsolver_samples.orders_raw_data
    LET formatString = '{0} {1} is {2} years old',
        inputs1 = array['John', 'Jane'],
        inputs2 = array['Smith', 'Johnson'],
        inputs3 = array[35, 32]
    WHERE $commit_time BETWEEN run_start_time() AND run_end_time()
    LIMIT 1;
```

#### Query result

<table><thead><tr><th>formatString</th><th>inputs1[]</th><th>inputs2[]</th><th width="161">inputs3[]</th><th>Output</th></tr></thead><tbody><tr><td>'{0} {1} is {2} years old'</td><td>array['John', 'Jane']</td><td>array['Smith', 'Johnson']</td><td>array[35, 32]</td><td>[<code>John Smith is 35 years old</code>, <code>Jane Johnson is 32 years old</code>]</td></tr></tbody></table>


---

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