Examples with DescribeMetadata com.google.cloud.spanner.pgadapter.metadata.DescribeMetadata used on opensource projects

Example 1 with DescribeMetadata

use of com.google.cloud.spanner.pgadapter.metadata.DescribeMetadata in project pgadapter by GoogleCloudPlatform.

the class IntermediatePreparedStatement method describe.

@Override
public DescribeMetadata describe() {
    Set<String> parameters = ImmutableSortedSet.<String>orderedBy(Comparator.comparing(o -> o.substring(1))).addAll(PARSER.getQueryParameters(this.parsedStatement.getSqlWithoutComments())).build();
    ResultSet columnsResultSet = null;
    try {
        if (this.parsedStatement.isQuery()) {
            Statement statement = Statement.of(this.parsedStatement.getSqlWithoutComments());
            columnsResultSet = connection.analyzeQuery(statement, QueryAnalyzeMode.PLAN);
        }
        boolean describeFailed = false;
        if (parameters.isEmpty()) {
            ensureParameterLength(0);
        } else if (parameters.size() != this.parameterDataTypes.length || Arrays.stream(this.parameterDataTypes).anyMatch(p -> p == 0)) {
            // Note: We are only asking the backend to parse the types if there is at least one
            // parameter
            // with unspecified type. Otherwise, we will rely on the types given in PARSE.
            // Transform the statement into a select statement that selects the parameters, and then
            // extract the types from the result set metadata.
            Statement selectParamsStatement = transformToSelectParams(parameters);
            if (selectParamsStatement == null) {
                // The transformation failed. Just rely on the types given in the PARSE message. If the
                // transformation failed because the statement was malformed, the backend will catch that
                // at
                // a later stage.
                describeFailed = true;
                ensureParameterLength(parameters.size());
            } else {
                try (ResultSet paramsResultSet = connection.analyzeQuery(selectParamsStatement, QueryAnalyzeMode.PLAN)) {
                    extractParameterTypes(paramsResultSet);
                } catch (SpannerException exception) {
                    // Ignore here and rely on the types given in PARSE.
                    describeFailed = true;
                    ensureParameterLength(parameters.size());
                }
            }
        }
        if (columnsResultSet != null) {
            return new DescribeStatementMetadata(this.parameterDataTypes, columnsResultSet);
        }
        if (this.parsedStatement.isUpdate() && (describeFailed || !Strings.isNullOrEmpty(this.name))) {
            // Let the backend analyze the statement if it is a named prepared statement or if the query
            // that was used to determine the parameter types failed, so we can return a reasonable
            // error
            // message if the statement is invalid. If it is the unnamed statement or getting the param
            // types succeeded, we will let the following EXECUTE message handle that, instead of
            // sending
            // the statement twice to the backend.
            connection.analyzeUpdate(Statement.of(this.parsedStatement.getSqlWithoutComments()), QueryAnalyzeMode.PLAN);
        }
        return new DescribeStatementMetadata(this.parameterDataTypes, null);
    } finally {
        if (columnsResultSet != null) {
            columnsResultSet.close();
        }
    }
}