1 /* Copyright 2017 The TensorFlow Authors. All Rights Reserved. 2 3 Licensed under the Apache License, Version 2.0 (the "License"); 4 you may not use this file except in compliance with the License. 5 You may obtain a copy of the License at 6 7 http://www.apache.org/licenses/LICENSE-2.0 8 9 Unless required by applicable law or agreed to in writing, software 10 distributed under the License is distributed on an "AS IS" BASIS, 11 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 12 See the License for the specific language governing permissions and 13 limitations under the License. 14 ==============================================================================*/ 15 #include "tensorflow/core/kernels/data/sql/sqlite_query_connection.h" 16 17 #include "tensorflow/core/framework/register_types.h" 18 #include "tensorflow/core/kernels/data/dataset.h" 19 #include "tensorflow/core/lib/strings/stringprintf.h" 20 21 namespace tensorflow { 22 23 namespace sql { 24 25 SqliteQueryConnection::SqliteQueryConnection() {} 26 27 SqliteQueryConnection::~SqliteQueryConnection() { 28 if (db_ != nullptr) db_->Unref(); 29 } 30 31 Status SqliteQueryConnection::Open(const string& data_source_name, 32 const string& query, 33 const DataTypeVector& output_types) { 34 if (db_ != nullptr) { 35 return errors::FailedPrecondition( 36 "Failed to open query connection: Connection already opened."); 37 } 38 TF_RETURN_IF_ERROR(Sqlite::Open( 39 data_source_name, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, &db_)); 40 query_ = query; 41 output_types_ = output_types; 42 return Status::OK(); 43 } 44 45 Status SqliteQueryConnection::Close() { 46 stmt_ = SqliteStatement(); 47 db_->Unref(); 48 db_ = nullptr; 49 return Status::OK(); 50 } 51 52 Status SqliteQueryConnection::GetNext(IteratorContext* ctx, 53 std::vector<Tensor>* out_tensors, 54 bool* end_of_sequence) { 55 if (!stmt_) TF_RETURN_IF_ERROR(PrepareQuery()); 56 TF_RETURN_IF_ERROR(stmt_.Step(end_of_sequence)); 57 if (!*end_of_sequence) { 58 for (int i = 0; i < column_count_; i++) { 59 DataType dt = output_types_[i]; 60 // TODO(mrry): Pass in the `IteratorContext::allocator()`. 61 Tensor tensor(ctx->allocator({}), dt, {}); 62 FillTensorWithResultSetEntry(dt, i, &tensor); 63 out_tensors->emplace_back(std::move(tensor)); 64 } 65 } 66 return Status::OK(); 67 } 68 69 Status SqliteQueryConnection::PrepareQuery() { 70 TF_RETURN_IF_ERROR(db_->Prepare(query_, &stmt_)); 71 int column_count = stmt_.ColumnCount(); 72 if (column_count != output_types_.size()) { 73 stmt_ = SqliteStatement(); 74 return errors::InvalidArgument(tensorflow::strings::Printf( 75 "The number of columns in query (%d) must match the number of " 76 "elements in output_types (%zu).", 77 column_count, output_types_.size())); 78 } 79 column_count_ = column_count; 80 return Status::OK(); 81 } 82 83 void SqliteQueryConnection::FillTensorWithResultSetEntry( 84 const DataType& data_type, int column_index, Tensor* tensor) { 85 #define CASE(T, M) \ 86 case DataTypeToEnum<T>::value: \ 87 tensor->scalar<T>()() = static_cast<T>(stmt_.M(column_index)); \ 88 break; 89 #define INT_CASE(T) CASE(T, ColumnInt) 90 #define DOUBLE_CASE(T) CASE(T, ColumnDouble) 91 #define STRING_CASE(T) CASE(T, ColumnString) 92 // clang-format off 93 switch (data_type) { 94 TF_CALL_int8(INT_CASE) 95 TF_CALL_uint8(INT_CASE) 96 TF_CALL_int16(INT_CASE) 97 TF_CALL_uint16(INT_CASE) 98 TF_CALL_int32(INT_CASE) 99 TF_CALL_uint32(INT_CASE) 100 TF_CALL_int64(INT_CASE) 101 TF_CALL_uint64(INT_CASE) 102 TF_CALL_float(DOUBLE_CASE) 103 TF_CALL_double(DOUBLE_CASE) 104 TF_CALL_string(STRING_CASE) 105 case DT_BOOL: 106 tensor->scalar<bool>()() = stmt_.ColumnInt(column_index) != 0; 107 break; 108 // Error preemptively thrown by SqlDatasetOp::MakeDataset in this case. 109 default: 110 LOG(FATAL) 111 << "Use of unsupported TensorFlow data type by 'SqlQueryConnection': " 112 << DataTypeString(data_type) << "."; 113 } 114 // clang-format on 115 } 116 117 } // namespace sql 118 119 } // namespace tensorflow 120
