Problem
You cannot delete data from a Delta table using JDBC from your local Eclipse environment. The same delete operation works when run in a notebook.
You can connect to Databricks from your local environment.
A select query works.
Integer count = namedlocalJdbcTemplate.queryForObject("SELECT COUNT(*) FROM <table-name> ", new MapSqlParameterSource(), Integer.class);
You attempt a delete operation and it fails.
namedlocalJdbcTemplate.update("DELETE FROM <table-name> WHERE id = :Id", parameters); where parameter is MapSqlParameterSource params = new MapSqlParameterSource(); params.addValue("Id", “001”);
You receive a SparkJDBCDriver error message.
org.springframework.jdbc.UncategorizedSQLException: PreparedStatementCallback; uncategorized SQLException for SQL [DELETE FROM <table-name> WHERE Id = ?]; SQL state [HY000]; error code [500051]; [Simba][SparkJDBCDriver](500051) ERROR processing query/statement. Error Code: 0, SQL state: Error running query: org.apache.spark.sql.AnalysisException: cannot resolve '`<table-name>.Id`' given input columns: []; line 1 pos 41; 'DeleteCommandEdge Delta[version=0, s3://<path-to-database>], ('<table-name>.Id = 001)
Cause
This error can occur when UseNativeQuery has a value of 0.
The ODBC driver parses the query and does some rewriting when UseNativeQuery has a value of 0. Some tools, like PowerBI, depend on this translation. For example, PowerBI generates standard ANSI SQL which needs translation to Spark SQL. It has the potential to add unnecessary overheard if the application already generates Spark SQL.
Solution
Set UseNativeQuery to a value of 1 in the JDBC connection string in your IDE. This forces the ODBC driver to pass the submitted query without rewriting it.
String CONNECTION_URL = "jdbc:spark://<server-hostname>:443/default;transportMode=http;ssl=1;httpPath=sql/protocolv1/o/0/xxxx-xxxxxx-xxxxxxxx;AuthMech=3;UID=token;PWD=<personal-access-token>;UseNativeQuery=1" Connection connection = null; connection = DriverManager.getConnection(CONNECTION_URL);
Review the Initializing the Driver Class Simba documentation for more information on establishing a JDBC connection.
After you set UseNativeQuery to a value of 1, you must rewrite your insert query so that it does not specify column names.
For example, INSERT INTO <table-name> VALUES (<?>,<?>,<?>,<?>,<?>,<?>,<?>,<?>).
This is because Spark SQL does not natively support column names when using the insert command.