ClickHouse / ClickHouse/clickhouse-java
In the JDBC query result set, columns of type AggregateFunction cannot be parsed normally
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Descripción
## Description
When creating a materialized view, specify the Select statement as follows:
```sql
SELECT
toDate(timestamp) AS date,
countState(*) AS count,
quantileState(0.9)(duration) AS tp90_duration_ms,
quantileState(0.99)(duration) AS tp99_duration_ms,
avgState(duration) AS avg_duration_ms,
maxState(duration) AS max_duration_ms,
minState(duration) AS min_duration_ms
FROM test.test_table_local
GROUP BY
date
```
This statement is queried directly with JDBC, and the final error is:
java.sql.SQLException: Failed to read value for column count
final debug result:
1. BinaryStreamReader.java -> readValue method
case AggregateFunction:
return (T)this.readBitmap(actualColumn);
2. readBitmap method
```java
private ClickHouseBitmap readBitmap(ClickHouseColumn column) throws IOException {
return ClickHouseBitmap.deserialize(this.input, ((ClickHouseColumn)column.getNestedColumns().get(0)).getDataType());
}
```
column.getNestedColumns() is empty
3.
### Error Log or Exception StackTrace
```
This statement is queried directly with JDBC, and the final error is:
java.sql.SQLException: Failed to read value for column count
```
### Expected Behaviour
### Code Example
```java
```
### Configuration
#### Client Configuration
```java
```
#### Environment
* [ ] Cloud
* Client version: 0.9.4
* Language version: 1.8
* OS: mac
#### ClickHouse Server
* ClickHouse Server version: 25.5.1
Guía de contribución
Línea de trabajo
Comienza con BinaryStreamReader.java, especialmente con readValue y readBitmap, y reproduce la consulta de la vista materializada usando ClickHouse Java client 0.9.4 contra ClickHouse 25.5.1. Inspecciona por qué AggregateFunction no tiene columnas anidadas; se considera terminado cuando JDBC pueda leer las columnas del resultado agregado sin la SQLException.
Escrito por el modelo de indexación a partir del texto del issue.
Evaluación
- Stack tecnológico
- java, sql
- Área
- database
- Tipo de issue
- Error
- Dificultad
- 3/5
- Tiempo estimado
- 1-2 días
- Estado de actividad
- Estancado
- Claridad
- Bastante claro
- Aptitud para principiantes
- 38/100