scalikejdbc-bigquery
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The document provides code examples for querying data from BigQuery using ScalikeJDBC and the BigQuery Java Client Library. It shows how to left join tables, use window functions to rank rows, bind parameters, and extract results. Issues addressed include incorrectly specifying the column for a join and not knowing how to bind a custom data type as a parameter.
scalikejdbc-bigquery
- 8. bq { select(p.result.*, t.result.*).from( (Post in dataset) as p ).leftJoin( (Tag in dataset) as t ).on(p.id, t.postId) } .one(Post(_)) .toMany(Tag.opt) .map(PostWithTags) .list .run(executor)
- 9. bq { select(p.result.*, t.result.*).from( (Post in dataset) as p ).leftJoin( (Tag in dataset) as t ).on(p.id, t.posssssstId) // wrong column name }
- 10. bq { select(p.result.*, t.result.*).from( (Post in dataset) as p ).leftJoin( (Tag in dataset) as t ).on(p.id, t.postId) .where // Don't know how to bind MyDataType as parameter .eq(t.name, MyDataType("some tag_name")) }
- 11. bq { select( // window function p.result.*, rank.over(orderBy(p.postedAt.desc)).as(sqls"rnk") ).from( (Post in dataset) as p ) } .map { resultSet => PostWithRank(Post(resultSet), resultSet.int(sqls"rnk")) } .list .run(executor)
- 13. Query Building (ScalikeJDBC) Execute using BigQuery Java Client Library (scalikejdbc-bigquery) Extract Result (scalikejdbc-bigquery)
- 23. // JDBC val statement = conn.prepareStatement( "select * from user where id = ? and name = ?" ) // bind parameters statement.setInt(1, 42) statement.setString(2, "John") // BigQuery Java Client Library val request = QueryRequest.newBuilder( "select * from user where id = ? and name = ?") .setPositionalParameters( Seq( QueryParameterValue.int64(42), QueryParameterValue.string("John") ).asJava ) .build()