Rename prevouts table to prevout, define schema and read/write.

Makefile.am

@@ -100,7 +100,7 @@ test_libbitcoin_database_test_SOURCES = \
     test/tables/archives/spend.cpp \
     test/tables/archives/transaction.cpp \
     test/tables/archives/txs.cpp \
-    test/tables/caches/prevouts.cpp \
+    test/tables/caches/prevout.cpp \
     test/tables/caches/validated_bk.cpp \
     test/tables/caches/validated_tx.cpp \
     test/tables/indexes/height.cpp \
@@ -237,7 +237,7 @@ include_bitcoin_database_tables_archives_HEADERS = \
 
 include_bitcoin_database_tables_cachesdir = ${includedir}/bitcoin/database/tables/caches
 include_bitcoin_database_tables_caches_HEADERS = \
-    include/bitcoin/database/tables/caches/prevouts.hpp \
+    include/bitcoin/database/tables/caches/prevout.hpp \
     include/bitcoin/database/tables/caches/validated_bk.hpp \
     include/bitcoin/database/tables/caches/validated_tx.hpp
 

builds/cmake/CMakeLists.txt

@@ -308,7 +308,7 @@ if (with-tests)
         "../../test/tables/archives/spend.cpp"
         "../../test/tables/archives/transaction.cpp"
         "../../test/tables/archives/txs.cpp"
-        "../../test/tables/caches/prevouts.cpp"
+        "../../test/tables/caches/prevout.cpp"
         "../../test/tables/caches/validated_bk.cpp"
         "../../test/tables/caches/validated_tx.cpp"
         "../../test/tables/indexes/height.cpp"

builds/msvc/vs2022/libbitcoin-database-test/libbitcoin-database-test.vcxproj

@@ -111,7 +111,7 @@
     <ClCompile Include="..\..\..\..\test\tables\archives\spend.cpp" />
     <ClCompile Include="..\..\..\..\test\tables\archives\transaction.cpp" />
     <ClCompile Include="..\..\..\..\test\tables\archives\txs.cpp" />
-    <ClCompile Include="..\..\..\..\test\tables\caches\prevouts.cpp" />
+    <ClCompile Include="..\..\..\..\test\tables\caches\prevout.cpp" />
     <ClCompile Include="..\..\..\..\test\tables\caches\validated_bk.cpp" />
     <ClCompile Include="..\..\..\..\test\tables\caches\validated_tx.cpp" />
     <ClCompile Include="..\..\..\..\test\tables\indexes\height.cpp" />

builds/msvc/vs2022/libbitcoin-database-test/libbitcoin-database-test.vcxproj.filters

@@ -156,7 +156,7 @@
     <ClCompile Include="..\..\..\..\test\tables\archives\txs.cpp">
       <Filter>src\tables\archives</Filter>
     </ClCompile>
-    <ClCompile Include="..\..\..\..\test\tables\caches\prevouts.cpp">
+    <ClCompile Include="..\..\..\..\test\tables\caches\prevout.cpp">
       <Filter>src\tables\caches</Filter>
     </ClCompile>
     <ClCompile Include="..\..\..\..\test\tables\caches\validated_bk.cpp">

builds/msvc/vs2022/libbitcoin-database/libbitcoin-database.vcxproj

@@ -133,7 +133,7 @@
     <ClInclude Include="..\..\..\..\include\bitcoin\database\tables\archives\spend.hpp" />
     <ClInclude Include="..\..\..\..\include\bitcoin\database\tables\archives\transaction.hpp" />
     <ClInclude Include="..\..\..\..\include\bitcoin\database\tables\archives\txs.hpp" />
-    <ClInclude Include="..\..\..\..\include\bitcoin\database\tables\caches\prevouts.hpp" />
+    <ClInclude Include="..\..\..\..\include\bitcoin\database\tables\caches\prevout.hpp" />
     <ClInclude Include="..\..\..\..\include\bitcoin\database\tables\caches\validated_bk.hpp" />
     <ClInclude Include="..\..\..\..\include\bitcoin\database\tables\caches\validated_tx.hpp" />
     <ClInclude Include="..\..\..\..\include\bitcoin\database\tables\context.hpp" />

builds/msvc/vs2022/libbitcoin-database/libbitcoin-database.vcxproj.filters

@@ -242,7 +242,7 @@
     <ClInclude Include="..\..\..\..\include\bitcoin\database\tables\archives\txs.hpp">
       <Filter>include\bitcoin\database\tables\archives</Filter>
     </ClInclude>
-    <ClInclude Include="..\..\..\..\include\bitcoin\database\tables\caches\prevouts.hpp">
+    <ClInclude Include="..\..\..\..\include\bitcoin\database\tables\caches\prevout.hpp">
       <Filter>include\bitcoin\database\tables\caches</Filter>
     </ClInclude>
     <ClInclude Include="..\..\..\..\include\bitcoin\database\tables\caches\validated_bk.hpp">

include/bitcoin/database.hpp

@@ -64,7 +64,7 @@
 #include <bitcoin/database/tables/archives/spend.hpp>
 #include <bitcoin/database/tables/archives/transaction.hpp>
 #include <bitcoin/database/tables/archives/txs.hpp>
-#include <bitcoin/database/tables/caches/prevouts.hpp>
+#include <bitcoin/database/tables/caches/prevout.hpp>
 #include <bitcoin/database/tables/caches/validated_bk.hpp>
 #include <bitcoin/database/tables/caches/validated_tx.hpp>
 #include <bitcoin/database/tables/indexes/height.hpp>

include/bitcoin/database/tables/caches/prevout.hpp

@@ -0,0 +1,77 @@
+/**
+ * Copyright (c) 2011-2025 libbitcoin developers (see AUTHORS)
+ *
+ * This file is part of libbitcoin.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#ifndef LIBBITCOIN_DATABASE_TABLES_OPTIONALS_BUFFER_HPP
+#define LIBBITCOIN_DATABASE_TABLES_OPTIONALS_BUFFER_HPP
+
+#include <bitcoin/system.hpp>
+#include <bitcoin/database/define.hpp>
+#include <bitcoin/database/primitives/primitives.hpp>
+#include <bitcoin/database/tables/schema.hpp>
+
+namespace libbitcoin {
+namespace database {
+namespace table {
+
+/// prevout is an array map index of previous outputs by block.
+struct prevout
+  : public array_map<schema::prevout>
+{
+    using tx = linkage<schema::tx>;
+    using spend = linkage<schema::spend_>;
+    using array_map<schema::prevout>::arraymap;
+
+    struct record
+      : public schema::prevout
+    {
+        inline bool from_data(reader& source) NOEXCEPT
+        {
+            coinbase = source.read_byte();
+            spend_fk = source.read_little_endian<spend::integer, spend::size>();
+            output_tx_fk = source.read_little_endian<tx::integer, tx::size>();
+            BC_ASSERT(source.get_read_position() == count());
+            return source;
+        }
+
+        inline bool to_data(finalizer& sink) const NOEXCEPT
+        {
+            sink.write_byte(coinbase);
+            sink.write_little_endian<spend::integer, spend::size>(spend_fk);
+            sink.write_little_endian<tx::integer, tx::size>(output_tx_fk);
+            BC_ASSERT(sink.get_write_position() == count());
+            return sink;
+        }
+
+        inline bool operator==(const record& other) const NOEXCEPT
+        {
+            return coinbase == other.coinbase
+                && spend_fk == other.spend_fk
+                && output_tx_fk == other.output_tx_fk;
+        }
+
+        bool coinbase{};
+        spend::integer spend_fk{};
+        tx::integer output_tx_fk{};
+    };
+};
+
+} // namespace table
+} // namespace database
+} // namespace libbitcoin
+
+#endif

include/bitcoin/database/tables/schema.hpp

@@ -63,6 +63,7 @@ namespace schema
 
     namespace caches
     {
+        constexpr auto prevout = "prevout";
         constexpr auto validated_bk = "validated_bk";
         constexpr auto validated_tx = "validated_tx";
     }
@@ -120,7 +121,6 @@ namespace schema
     constexpr size_t bk_slab = 3;   // ->validated_bk record.
     constexpr size_t tx_slab = 5;   // ->validated_tk record.
     constexpr size_t neutrino_ = 5; // ->neutrino record.
-    ////constexpr size_t buffer_ = 5;   // ->buffer record (guestimate).
 
     /// Search keys.
     constexpr size_t hash = system::hash_size;
@@ -355,6 +355,22 @@ namespace schema
         static_assert(minrow == 23u);
     };
 
+    // record arraymap
+    struct prevout
+    {
+        static constexpr size_t pk = schema::spend_;
+        static constexpr size_t sk = zero;
+        static constexpr size_t minsize =
+            schema::bit + // TODO: merge bit.
+            schema::spend_ +
+            schema::tx;
+        static constexpr size_t minrow = minsize;
+        static constexpr size_t size = minsize;
+        static constexpr linkage<pk> count() NOEXCEPT { return 1; }
+        static_assert(minsize == 9u);
+        static_assert(minrow == 9u);
+    };
+
     // slab hashmap
     struct neutrino
     {

test/tables/caches/prevout.cpp

@@ -0,0 +1,26 @@
+/**
+ * Copyright (c) 2011-2025 libbitcoin developers (see AUTHORS)
+ *
+ * This file is part of libbitcoin.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+#include "../../test.hpp"
+#include "../../mocks/chunk_storage.hpp"
+
+BOOST_AUTO_TEST_SUITE(prevout_tests)
+
+using namespace system;
+
+BOOST_AUTO_TEST_SUITE_END()