JDBC driver passes decimal value without quotes, then where clause works wrong

[anesterenok]

• jdbc-v2
• jdbc-read

Description

I have a MergeTree() test table with Decimal(38,10) values like 12345678901234567001.1234567890.

When I execute a PreparedStatement like:

        try (PreparedStatement pstmt = conn.prepareStatement("select * from test_table where col_decimal < ?")) {
            pstmt.setBigDecimal(1, new BigDecimal("12345678901234567008.1234567890"));
            ResultSet rs = pstmt.executeQuery();
...

no rows are returned (though you may see that 12345678901234567001.1234567890 < 12345678901234567008.1234567890)

I believe this is because the JDBC driver sends the following statement to the database:

http-outgoing-0 >> "User-Agent: ClickHouse JDBC Driver V2/0.8.6 clickhouse-java-v2/0.8.6 (Linux; jvm:17.0.7) Apache-HttpClient/5.3.1[\r][\n]"
...
http-outgoing-0 >> "SELECT * FROM test_table WHERE col_decimal < 12345678901234567008.1234567890[\r][\n]"
http-outgoing-0 >> "0[\r][\n]"
http-outgoing-0 >> "[\r][\n]"
http-outgoing-0 << "HTTP/1.1 200 OK[\r][\n]"
http-outgoing-0 << "X-ClickHouse-Summary: {"read_rows":"11","read_bytes":"187","written_rows":"0","written_bytes":"0","total_rows_to_read":"11","result_rows":"0","result_bytes":"0","elapsed_ns":"3362900"}[\r][\n]"

If I execute the same statement in SQL client, I also do not receive the rows. However, if I quote the literal and execute:

SELECT * FROM test_table WHERE col_decimal < '12345678901234567008.1234567890'

then rows are filtered correctly.

So it looks like a bug on JDBC driver side, it should had quoted the decimal literal.

Workaround

If I set PreparedStatement param as String, not BigDecimal, like this:

        try (PreparedStatement pstmt = conn.prepareStatement("select * from test_table where col_decimal < ?")) {
            pstmt.setString(1, "12345678901234567008.1234567890");
            ResultSet rs = pstmt.executeQuery();
...

then the driver does send a quoted literal and filter works fine. But it's certainly not how things are supposed to be, setBigDecimal() should have worked as well.

Expected Behaviour

Row with value 12345678901234567001.1234567890 is returned by filter.

Code Example

see above

Configuration

Client Configuration

Environment

• Cloud
• Client version: JDBC driver clickhouse-jdbc-0.8.6-all.jar
• Language version: JDK 17
• OS: Linux

ClickHouse Server

• ClickHouse Server version: 25.8.16.34
• ClickHouse Server non-default settings, if any: none
• CREATE TABLE statements for tables involved:
• Sample data for all these tables, use clickhouse-obfuscator if necessary