feat(jdbc): JdbcExporter, matching the CSV and Parquet exporters

Aberta
  • Algo errado?
#567 0 comentários 0 reações 0 responsáveis Ver no GitHub

Mantenedores costumam responder em até 1 dia

Ninguém assumiu esta issue ainda.

Avaliação

Dificuldade
5/5
Tempo estimado
Mais de uma semana
Facilidade para iniciantes
25/100
Tipo de issue
Funcionalidade
Clareza
Razoavelmente clara
Status de atividade
Ativa
Stack de tecnologia
java, sql
Domínio
database

Direção de pesquisa

Start by comparing the existing JdbcImporter and JdbcImportOptions with the CSV and Parquet exporter APIs to locate the JDBC module’s conventions. Then review the import type mapping and exporter progress listener patterns before defining the export API and binder behavior. Done means exporting rows into a caller-provided table in batches with validity-aware nulls, transaction rollback on failure, restored auto-commit, and opt-in DDL support.

Escrita pelo modelo de indexação a partir do texto da issue.

Descrição

enhancement

vortex-jdbc only has JdbcImporter/JdbcImportOptions; csv and parquet each have an importer and an exporter. Add JdbcExporter + JdbcExportOptions for symmetry: read a Vortex file and move its rows into a table in a JDBC database over a caller-supplied Connection.

API sketch

JdbcExportOptions opts = JdbcExportOptions.defaults()
        .withBatchSize(5_000)
        .withBinder(JdbcBinder.standard()
                .with(DType.Extension.class, (ps, i, value) -> ps.setObject(i, value)));

JdbcExporter.export(vortexPath, connection, "ohlc", opts);
  • Options are a final class with a private constructor, defaults() and withXxx copies, as everywhere else. The target table is a required argument of export, not an option (confirm that CsvExporter/ParquetExporter take their target the same way).
  • Binder (callback): a small functional interface that sets one value on a PreparedStatement. JdbcBinder.standard() covers primitives, strings, decimals, booleans and dates. A user overrides only the types their database needs special handling for (Postgres arrays, setObject for timestamps).
  • DDL helper, not automatic: a DType to SQL type function plus createTableSql(name, dtype) returns a CREATE TABLE string. The exporter never creates or alters a table on its own; creation is opt-in.

Behavior

  • Appends to an existing table with INSERT INTO t (cols...) VALUES (?, ...) through a PreparedStatement. Nulls follow the validity mask.
  • One transaction for the whole export: remember the connection's auto-commit setting, setAutoCommit(false), addBatch() per row, executeBatch() every batchSize rows, commit() at the end, rollback() and rethrow on failure, and restore auto-commit in a finally. The connection belongs to the caller. A failed export leaves nothing behind.
  • ProgressListener, as in the other exporters.

Open design questions

  • Reverse type mapping DType to SQL type (the inverse of SqlTypeToDType); it varies by database.
  • Create-if-missing vs truncate vs fail-if-exists: all opt-in, append is the default.
  • A withCommitEvery(n) option for very large exports, if a long-lived transaction proves a problem. Not in the first cut.

Not needed for the jdbc:vortex: driver work (#566). No demand yet, so this waits until someone needs it.

Linguagem predominante
Java
Estrelas
3
Forks
2
Merge médio
14h 59min
PRs com merge (30d)
137

Preparar o ambiente

Primeiros passos

  1. Leia a issue inteira e depois o guia de contribuição do projeto.
  2. Comente na issue dizendo que vai assumir — evita que duas pessoas façam o mesmo trabalho.
  3. Faça um fork do repositório e trabalhe em uma branch.
  4. Abra um pull request que referencie o número da issue.

Mais de dfa1/vortex-java

Todas as issues de dfa1/vortex-java

Issues semelhantes

Mais issues de Java

Receba novas issues na sua caixa de entrada

Um resumo curto de issues do GitHub para quem está começando.