```
ROW a="b c d"
| DISSECT a "%{b} %{} %{d}"
```
returns

```
       a       |       b       |               |       d       
---------------+---------------+---------------+---------------
b c d          |b              |null           |d 
```

it should ignore the empty pattern instead, and only return `a, b, d`
x-pack/plugin/esql/src/test/java/org/elasticsearch/xpack/esql/parser/StatementParserTests.java
"row x = ?",
            List.of(new TypedParamValue("time_duration", "bar seconds")),
            "Cannot parse [bar seconds] to TIME_DURATION"
        );
        expectError(
            "row x = ?",
            List.of(new TypedParamValue("date_period", "2 minutes")),
            "Cannot parse [2 minutes] to DATE_PERIOD, did you mean TIME_DURATION?"
        );
        expectError(
            "row x = ?",
            List.of(new TypedParamValue("time_duration", "11 months")),
            "Cannot parse [11 months] to TIME_DURATION, did you mean DATE_PERIOD?"
        );
    }
    public void testMissingInputParams() {
        expectError("row x = ?, y = ?", List.of(new TypedParamValue("integer", 1)), "Not enough actual parameters 1");
    }
    private void assertIdentifierAsIndexPattern(String identifier, String statement) {
        LogicalPlan from = statement(statement);
        assertThat(from, instanceOf(EsqlUnresolvedRelation.class));
        EsqlUnresolvedRelation table = (EsqlUnresolvedRelation) from;
        assertThat(table.table().index(), is(identifier));
    }
    private LogicalPlan statement(String e) {
        return statement(e, List.of());
    }
    private LogicalPlan statement(String e, List<TypedParamValue> params) {
        return parser.createStatement(e, params);
    }