private/google/spanner/v1/result_set.proto
// Copyright 2020 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
syntax = "proto3";
package google.spanner.v1;
import "google/protobuf/struct.proto";
import "google/spanner/v1/query_plan.proto";
import "google/spanner/v1/transaction.proto";
import "google/spanner/v1/type.proto";
import "google/api/annotations.proto";
option cc_enable_arenas = true;
option csharp_namespace = "Google.Cloud.Spanner.V1";
option go_package = "google.golang.org/genproto/googleapis/spanner/v1;spanner";
option java_multiple_files = true;
option java_outer_classname = "ResultSetProto";
option java_package = "com.google.spanner.v1";
option php_namespace = "Google\\Cloud\\Spanner\\V1";
option ruby_package = "Google::Cloud::Spanner::V1";
// Results from [Read][google.spanner.v1.Spanner.Read] or
// [ExecuteSql][google.spanner.v1.Spanner.ExecuteSql].
message ResultSet {
// Metadata about the result set, such as row type information.
ResultSetMetadata metadata = 1;
// Each element in `rows` is a row whose format is defined by
// [metadata.row_type][google.spanner.v1.ResultSetMetadata.row_type]. The ith element
// in each row matches the ith field in
// [metadata.row_type][google.spanner.v1.ResultSetMetadata.row_type]. Elements are
// encoded based on type as described
// [here][google.spanner.v1.TypeCode].
repeated google.protobuf.ListValue rows = 2;
// Query plan and execution statistics for the SQL statement that
// produced this result set. These can be requested by setting
// [ExecuteSqlRequest.query_mode][google.spanner.v1.ExecuteSqlRequest.query_mode].
// DML statements always produce stats containing the number of rows
// modified, unless executed using the
// [ExecuteSqlRequest.QueryMode.PLAN][google.spanner.v1.ExecuteSqlRequest.QueryMode.PLAN] [ExecuteSqlRequest.query_mode][google.spanner.v1.ExecuteSqlRequest.query_mode].
// Other fields may or may not be populated, based on the
// [ExecuteSqlRequest.query_mode][google.spanner.v1.ExecuteSqlRequest.query_mode].
ResultSetStats stats = 3;
}
// Partial results from a streaming read or SQL query. Streaming reads and
// SQL queries better tolerate large result sets, large rows, and large
// values, but are a little trickier to consume.
message PartialResultSet {
// Metadata about the result set, such as row type information.
// Only present in the first response.
ResultSetMetadata metadata = 1;
// A streamed result set consists of a stream of values, which might
// be split into many `PartialResultSet` messages to accommodate
// large rows and/or large values. Every N complete values defines a
// row, where N is equal to the number of entries in
// [metadata.row_type.fields][google.spanner.v1.StructType.fields].
//
// Most values are encoded based on type as described
// [here][google.spanner.v1.TypeCode].
//
// It is possible that the last value in values is "chunked",
// meaning that the rest of the value is sent in subsequent
// `PartialResultSet`(s). This is denoted by the [chunked_value][google.spanner.v1.PartialResultSet.chunked_value]
// field. Two or more chunked values can be merged to form a
// complete value as follows:
//
// * `bool/number/null`: cannot be chunked
// * `string`: concatenate the strings
// * `list`: concatenate the lists. If the last element in a list is a
// `string`, `list`, or `object`, merge it with the first element in
// the next list by applying these rules recursively.
// * `object`: concatenate the (field name, field value) pairs. If a
// field name is duplicated, then apply these rules recursively
// to merge the field values.
//
// Some examples of merging:
//
// # Strings are concatenated.
// "foo", "bar" => "foobar"
//
// # Lists of non-strings are concatenated.
// [2, 3], [4] => [2, 3, 4]
//
// # Lists are concatenated, but the last and first elements are merged
// # because they are strings.
// ["a", "b"], ["c", "d"] => ["a", "bc", "d"]
//
// # Lists are concatenated, but the last and first elements are merged
// # because they are lists. Recursively, the last and first elements
// # of the inner lists are merged because they are strings.
// ["a", ["b", "c"]], [["d"], "e"] => ["a", ["b", "cd"], "e"]
//
// # Non-overlapping object fields are combined.
// {"a": "1"}, {"b": "2"} => {"a": "1", "b": 2"}
//
// # Overlapping object fields are merged.
// {"a": "1"}, {"a": "2"} => {"a": "12"}
//
// # Examples of merging objects containing lists of strings.
// {"a": ["1"]}, {"a": ["2"]} => {"a": ["12"]}
//
// For a more complete example, suppose a streaming SQL query is
// yielding a result set whose rows contain a single string
// field. The following `PartialResultSet`s might be yielded:
//
// {
// "metadata": { ... }
// "values": ["Hello", "W"]
// "chunked_value": true
// "resume_token": "Af65..."
// }
// {
// "values": ["orl"]
// "chunked_value": true
// "resume_token": "Bqp2..."
// }
// {
// "values": ["d"]
// "resume_token": "Zx1B..."
// }
//
// This sequence of `PartialResultSet`s encodes two rows, one
// containing the field value `"Hello"`, and a second containing the
// field value `"World" = "W" + "orl" + "d"`.
repeated google.protobuf.Value values = 2;
// If true, then the final value in [values][google.spanner.v1.PartialResultSet.values] is chunked, and must
// be combined with more values from subsequent `PartialResultSet`s
// to obtain a complete field value.
bool chunked_value = 3;
// Streaming calls might be interrupted for a variety of reasons, such
// as TCP connection loss. If this occurs, the stream of results can
// be resumed by re-sending the original request and including
// `resume_token`. Note that executing any other transaction in the
// same session invalidates the token.
bytes resume_token = 4;
// Query plan and execution statistics for the statement that produced this
// streaming result set. These can be requested by setting
// [ExecuteSqlRequest.query_mode][google.spanner.v1.ExecuteSqlRequest.query_mode] and are sent
// only once with the last response in the stream.
// This field will also be present in the last response for DML
// statements.
ResultSetStats stats = 5;
}
// Metadata about a [ResultSet][google.spanner.v1.ResultSet] or [PartialResultSet][google.spanner.v1.PartialResultSet].
message ResultSetMetadata {
// Indicates the field names and types for the rows in the result
// set. For example, a SQL query like `"SELECT UserId, UserName FROM
// Users"` could return a `row_type` value like:
//
// "fields": [
// { "name": "UserId", "type": { "code": "INT64" } },
// { "name": "UserName", "type": { "code": "STRING" } },
// ]
StructType row_type = 1;
// If the read or SQL query began a transaction as a side-effect, the
// information about the new transaction is yielded here.
Transaction transaction = 2;
}
// Additional statistics about a [ResultSet][google.spanner.v1.ResultSet] or [PartialResultSet][google.spanner.v1.PartialResultSet].
message ResultSetStats {
// [QueryPlan][google.spanner.v1.QueryPlan] for the query associated with this result.
QueryPlan query_plan = 1;
// Aggregated statistics from the execution of the query. Only present when
// the query is profiled. For example, a query could return the statistics as
// follows:
//
// {
// "rows_returned": "3",
// "elapsed_time": "1.22 secs",
// "cpu_time": "1.19 secs"
// }
google.protobuf.Struct query_stats = 2;
// The number of rows modified by the DML statement.
oneof row_count {
// Standard DML returns an exact count of rows that were modified.
int64 row_count_exact = 3;
// Partitioned DML does not offer exactly-once semantics, so it
// returns a lower bound of the rows modified.
int64 row_count_lower_bound = 4;
}
}