14 #ifndef PQXX_H_TRANSACTION_BASE 15 #define PQXX_H_TRANSACTION_BASE 17 #if !defined(PQXX_HEADER_PRE) 18 # error "Include libpqxx headers as <pqxx/header>, not <pqxx/header.hxx>." 21 #include <string_view> 33 #include "pqxx/connection.hxx" 34 #include "pqxx/internal/concat.hxx" 35 #include "pqxx/internal/encoding_group.hxx" 36 #include "pqxx/isolation.hxx" 37 #include "pqxx/result.hxx" 38 #include "pqxx/row.hxx" 39 #include "pqxx/stream_from.hxx" 40 #include "pqxx/util.hxx" 44 class transaction_subtransaction;
45 class transaction_sql_cursor;
46 class transaction_stream_to;
47 class transaction_transaction_focus;
56 class transaction_focus;
120 template<
typename... ARGS> [[nodiscard]]
auto esc(ARGS &&...args)
const 123 return conn().esc(std::forward<ARGS>(args)...);
138 template<
typename... ARGS> [[nodiscard]]
auto esc_raw(ARGS &&...args)
const 140 return conn().esc_raw(std::forward<ARGS>(args)...);
147 [[nodiscard, deprecated(
"Use unesc_bin() instead.")]] std::string
150 #include "pqxx/internal/ignore-deprecated-pre.hxx" 151 return conn().unesc_raw(text);
152 #include "pqxx/internal/ignore-deprecated-post.hxx" 161 return conn().unesc_bin(text);
168 [[nodiscard, deprecated(
"Use unesc_bin() instead.")]] std::string
171 #include "pqxx/internal/ignore-deprecated-pre.hxx" 172 return conn().unesc_raw(text);
173 #include "pqxx/internal/ignore-deprecated-post.hxx" 180 [[nodiscard]] std::basic_string<std::byte>
unesc_bin(
char const text[])
182 return conn().unesc_bin(text);
187 template<
typename T> [[nodiscard]] std::string
quote(T
const &t)
const 189 return conn().quote(t);
193 "Use std::basic_string<std::byte> instead of binarystring.")]] std::string
200 [[deprecated(
"Use quote(std::basic_string_view<std::byte>).")]] std::string
201 quote_raw(
unsigned char const bin[], std::size_t len)
const 207 [[deprecated(
"Use quote(std::basic_string_view<std::byte>).")]] std::string
208 quote_raw(
zview bin)
const;
210 #if defined(PQXX_HAVE_CONCEPTS) 213 template<binary DATA>
214 [[nodiscard]] std::string quote_raw(DATA
const &data)
const 216 return conn().quote_raw(data);
221 [[nodiscard]] std::string
quote_name(std::string_view identifier)
const 223 return conn().quote_name(identifier);
227 [[nodiscard]] std::string
228 esc_like(std::string_view bin,
char escape_char =
'\\')
const 230 return conn().esc_like(bin, escape_char);
265 [[deprecated(
"The desc parameter is going away.")]]
result 266 exec(std::string_view query, std::string_view desc);
275 #include "pqxx/internal/ignore-deprecated-pre.hxx" 276 return exec(query, std::string_view{});
277 #include "pqxx/internal/ignore-deprecated-post.hxx" 287 "Pass your query as a std::string_view, not stringstream.")]]
result 288 exec(std::stringstream
const &query, std::string_view desc)
290 #include "pqxx/internal/ignore-deprecated-pre.hxx" 291 return exec(query.str(), desc);
292 #include "pqxx/internal/ignore-deprecated-post.hxx" 301 [[deprecated(
"The desc parameter is going away.")]]
result 304 #include "pqxx/internal/ignore-deprecated-pre.hxx" 305 return exec_n(0, query, desc);
306 #include "pqxx/internal/ignore-deprecated-post.hxx" 324 [[deprecated(
"The desc parameter is going away.")]]
row 327 #include "pqxx/internal/ignore-deprecated-pre.hxx" 328 return exec_n(1, query, desc).
front();
329 #include "pqxx/internal/ignore-deprecated-post.hxx" 347 [[deprecated(
"The desc parameter is going away.")]]
result 358 #include "pqxx/internal/ignore-deprecated-pre.hxx" 359 return exec_n(rows, query, std::string_view{});
360 #include "pqxx/internal/ignore-deprecated-post.hxx" 367 template<
typename TYPE>
368 [[deprecated(
"The desc parameter is going away.")]] TYPE
371 #include "pqxx/internal/ignore-deprecated-pre.hxx" 372 row const r{exec1(query, desc)};
373 #include "pqxx/internal/ignore-deprecated-post.hxx" 374 if (std::size(r) != 1)
376 "Queried single value from result with ", std::size(r),
" columns.")};
377 return r[0].as<TYPE>();
386 row const r{exec1(query)};
387 if (std::size(r) != 1)
389 "Queried single value from result with ", std::size(r),
" columns.")};
390 return r[0].as<TYPE>();
441 template<
typename... TYPE>
442 [[nodiscard]]
auto stream(std::string_view query) &
445 return pqxx::internal::owning_stream_input_iteration<TYPE...>{
446 std::unique_ptr<stream_from>{
471 template<
typename CALLABLE>
472 inline auto for_each(std::string_view query, CALLABLE &&func)
476 param_types
const *
const sample{
nullptr};
477 auto data_stream{stream_like(query, sample)};
478 for (
auto const &fields : data_stream) std::apply(func, fields);
510 template<
typename... Args>
result exec_params(
zview query, Args &&...args)
522 return exec_params_n(1, query, std::forward<Args>(args)...).
front();
530 return exec_params_n(0, query, std::forward<Args>(args)...);
536 template<
typename... Args>
539 auto const r{exec_params(query, std::forward<Args>(args)...)};
540 check_rowcount_params(rows, std::size(r));
578 template<
typename... Args>
582 return internal_exec_prepared(statement, pp.
make_c_params());
588 template<
typename... Args>
591 return exec_prepared_n(1, statement, std::forward<Args>(args)...).
front();
597 template<
typename... Args>
600 return exec_prepared_n(0, statement, std::forward<Args>(args)...);
607 template<
typename... Args>
611 auto const r{exec_prepared(statement, std::forward<Args>(args)...)};
612 check_rowcount_prepared(statement, rows, std::size(r));
622 void process_notice(
char const msg[])
const { m_conn.process_notice(msg); }
648 "Set transaction-local variables using SQL SET statements.")]]
void 649 set_variable(std::string_view var, std::string_view value);
655 [[deprecated(
"Read variables using SQL SHOW statements.")]] std::string
656 get_variable(std::string_view);
660 [[nodiscard]] std::string_view
name() const &noexcept {
return m_name; }
669 std::shared_ptr<std::string> rollback_cmd) :
670 m_conn{c}, m_name{tname}, m_rollback_cmd{rollback_cmd}
685 void register_transaction();
688 void close() noexcept;
691 virtual void do_commit() = 0;
697 virtual void do_abort();
702 m_rollback_cmd = cmd;
706 result direct_exec(std::string_view, std::string_view desc =
""sv);
708 direct_exec(std::shared_ptr<std::string>, std::string_view desc =
""sv);
719 PQXX_PRIVATE
void check_pending_error();
722 internal_exec_prepared(
zview statement, internal::c_params
const &args);
724 result internal_exec_params(
zview query, internal::c_params
const &args);
727 void check_rowcount_prepared(
733 check_rowcount_params(std::size_t expected_rows, std::size_t actual_rows);
736 [[nodiscard]] std::string description()
const;
738 friend class pqxx::internal::gate::transaction_transaction_focus;
741 PQXX_PRIVATE
void register_pending_error(
zview) noexcept;
742 PQXX_PRIVATE
void register_pending_error(std::string &&) noexcept;
745 template<typename... ARGS>
746 auto stream_like(
std::string_view query,
std::tuple<ARGS...> const *)
748 return stream<ARGS...>(query);
759 status m_status = status::active;
760 bool m_registered =
false;
762 std::string m_pending_error;
765 std::shared_ptr<std::string> m_rollback_cmd;
767 static constexpr std::string_view s_type_name{
"transaction"sv};
774 std::string_view transaction_base::query_value<std::string_view>(
775 zview query, std::string_view desc) =
delete;
778 zview transaction_base::query_value<zview>(
779 zview query, std::string_view desc) =
delete;
787 template<pqxx::isolation_level isolation, pqxx::write_policy rw>
792 inline constexpr
zview begin_cmd<read_committed, write_policy::read_write>{
795 inline constexpr
zview begin_cmd<read_committed, write_policy::read_only>{
796 "BEGIN READ ONLY"_zv};
798 inline constexpr
zview begin_cmd<repeatable_read, write_policy::read_write>{
799 "BEGIN ISOLATION LEVEL REPEATABLE READ"_zv};
801 inline constexpr
zview begin_cmd<repeatable_read, write_policy::read_only>{
802 "BEGIN ISOLATION LEVEL REPEATABLE READ READ ONLY"_zv};
804 inline constexpr
zview begin_cmd<serializable, write_policy::read_write>{
805 "BEGIN ISOLATION LEVEL SERIALIZABLE"_zv};
807 inline constexpr
zview begin_cmd<serializable, write_policy::read_only>{
808 "BEGIN ISOLATION LEVEL SERIALIZABLE READ ONLY"_zv};
Stream data from the database.
Definition: stream_from.hxx:77
std::basic_string_view< std::byte > bytes_view() const
Read data as a std::basic_string_view<std::byte>.
Definition: binarystring.hxx:178
Base class for things that monopolise a transaction's attention.
Definition: transaction_focus.hxx:28
row exec_prepared1(zview statement, Args &&...args)
Execute a prepared statement, and expect a single-row result.
Definition: transaction_base.hxx:589
auto esc_raw(ARGS &&...args) const
Escape binary data for use as SQL string literal in this transaction.
Definition: transaction_base.hxx:138
std::string quote_raw(unsigned char const bin[], std::size_t len) const
Binary-escape and quote a binary string for use as an SQL constant.
Definition: transaction_base.hxx:201
The home of all libpqxx classes, functions, templates, etc.
Definition: array.hxx:26
Reference to one row in a result.
Definition: row.hxx:46
static stream_from query(transaction_base &tx, std::string_view q)
Factory: Execute query, and stream the results.
Definition: stream_from.hxx:93
Connection to a database.
Definition: connection.hxx:185
std::string unesc_raw(zview text) const
Unescape binary data, e.g. from a table field or notification payload.
Definition: transaction_base.hxx:148
std::basic_string< std::byte > unesc_bin(zview text)
Unescape binary data, e.g. from a table field or notification payload.
Definition: transaction_base.hxx:159
result exec0(zview query)
Execute command, which should return zero rows of data.
Definition: transaction_base.hxx:315
pqxx::internal::c_params make_c_params() const
For internal use: Generate a params object for use in calls.
Definition: params.cxx:96
row exec_params1(zview query, Args &&...args)
Definition: transaction_base.hxx:520
std::string quote_name(std::string_view identifier) const
Escape an SQL identifier for use in a query.
Definition: transaction_base.hxx:221
TYPE query_value(zview query)
Perform query, expecting exactly 1 row with 1 field, and convert it.
Definition: transaction_base.hxx:384
std::string quote(binarystring const &t) const
Definition: transaction_base.hxx:194
row exec1(zview query, std::string_view desc)
Execute command returning a single row of data.
Definition: transaction_base.hxx:325
const zview begin_cmd
The SQL command for starting a given type of transaction.
result exec_prepared(zview statement, Args &&...args)
Execute a prepared statement, with optional arguments.
Definition: transaction_base.hxx:579
void process_notice(zview msg) const
Have connection process a warning message.
Definition: transaction_base.hxx:625
result exec_params_n(std::size_t rows, zview query, Args &&...args)
Definition: transaction_base.hxx:537
std::string esc_like(std::string_view bin, char escape_char='\\') const
Escape string for literal LIKE match.
Definition: transaction_base.hxx:228
result exec0(zview query, std::string_view desc)
Execute command, which should return zero rows of data.
Definition: transaction_base.hxx:302
Definition: connection.hxx:99
result exec_prepared_n(result::size_type rows, zview statement, Args &&...args)
Execute a prepared statement, expect a result with given number of rows.
Definition: transaction_base.hxx:609
TYPE query_value(zview query, std::string_view desc)
Perform query, expecting exactly 1 row with 1 field, and convert it.
Definition: transaction_base.hxx:369
result_size_type size_type
Definition: result.hxx:76
Error in usage of libpqxx library, similar to std::logic_error.
Definition: except.hxx:173
std::string quote(T const &t) const
Represent object as SQL string, including quoting & escaping.
Definition: transaction_base.hxx:187
Interface definition (and common code) for "transaction" classes.
Definition: transaction_base.hxx:77
auto for_each(std::string_view query, CALLABLE &&func)
Perform a streaming query, and for each result row, call func.
Definition: transaction_base.hxx:472
decltype(strip_types(std::declval< TYPES... >())) strip_types_t
Take a tuple type and apply strip_t to its component types.
Definition: util.hxx:519
std::basic_string< std::byte > unesc_bin(char const text[])
Unescape binary data, e.g. from a table field or notification payload.
Definition: transaction_base.hxx:180
transaction_base(connection &c, std::string_view tname, std::shared_ptr< std::string > rollback_cmd)
Create a transaction (to be called by implementation classes only).
Definition: transaction_base.hxx:667
Result set containing data returned by a query or command.
Definition: result.hxx:73
result exec(std::stringstream const &query, std::string_view desc)
Execute a command.
Definition: transaction_base.hxx:288
Marker-type wrapper: zero-terminated std::string_view.
Definition: zview.hxx:37
Internal items for libpqxx' own use. Do not use these yourself.
Definition: composite.hxx:82
std::string_view name() const &noexcept
Transaction name, if you passed one to the constructor; or empty string.
Definition: transaction_base.hxx:660
reference front() const noexcept
Definition: row.cxx:60
void set_rollback_cmd(std::shared_ptr< std::string > cmd)
Set the rollback command.
Definition: transaction_base.hxx:700
result exec(std::string_view query)
Execute a command.
Definition: transaction_base.hxx:273
result exec_prepared0(zview statement, Args &&...args)
Execute a prepared statement, and expect a result with zero rows.
Definition: transaction_base.hxx:598
std::string unesc_raw(char const *text) const
Unescape binary data, e.g. from a table field or notification payload.
Definition: transaction_base.hxx:169
result exec_n(result::size_type rows, zview query)
Execute command, expect given number of rows.
Definition: transaction_base.hxx:356
constexpr connection & conn() const noexcept
The connection in which this transaction lives.
Definition: transaction_base.hxx:629
row exec1(zview query)
Execute command returning a single row of data.
Definition: transaction_base.hxx:339
auto stream(std::string_view query) &
Execute a query, and loop over the results row by row.
Definition: transaction_base.hxx:442
Binary data corresponding to PostgreSQL's "BYTEA" binary-string type.
Definition: binarystring.hxx:58
std::basic_string_view< std::byte > binary_cast(TYPE const &data)
Cast binary data to a type that libpqxx will recognise as binary.
Definition: util.hxx:296
result exec_params0(zview query, Args &&...args)
Definition: transaction_base.hxx:528
Build a parameter list for a parameterised or prepared statement.
Definition: params.hxx:219