libpqxx
The C++ client library for PostgreSQL
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Classes | |
struct | pqxx::failure |
Run-time failure encountered by libpqxx, similar to std::runtime_error. More... | |
struct | pqxx::broken_connection |
Exception class for lost or failed backend connection. More... | |
struct | pqxx::protocol_violation |
Exception class for micommunication with the server. More... | |
struct | pqxx::variable_set_to_null |
The caller attempted to set a variable to null, which is not allowed. More... | |
class | pqxx::sql_error |
Exception class for failed queries. More... | |
struct | pqxx::in_doubt_error |
"Help, I don't know whether transaction was committed successfully!" More... | |
struct | pqxx::transaction_rollback |
The backend saw itself forced to roll back the ongoing transaction. More... | |
struct | pqxx::serialization_failure |
Transaction failed to serialize. Please retry it. More... | |
struct | pqxx::statement_completion_unknown |
We can't tell whether our last statement succeeded. More... | |
struct | pqxx::deadlock_detected |
The ongoing transaction has deadlocked. Retrying it may help. More... | |
struct | pqxx::internal_error |
Internal error in libpqxx library. More... | |
struct | pqxx::usage_error |
Error in usage of libpqxx library, similar to std::logic_error. More... | |
struct | pqxx::argument_error |
Invalid argument passed to libpqxx, similar to std::invalid_argument. More... | |
struct | pqxx::conversion_error |
Value conversion failed, e.g. when converting "Hello" to int. More... | |
struct | pqxx::unexpected_null |
Could not convert null value: target type does not support null. More... | |
struct | pqxx::conversion_overrun |
Could not convert value to string: not enough buffer space. More... | |
struct | pqxx::range_error |
Something is out of range, similar to std::out_of_range. More... | |
struct | pqxx::unexpected_rows |
Query returned an unexpected number of rows. More... | |
struct | pqxx::feature_not_supported |
Database feature not supported in current setup. More... | |
struct | pqxx::data_exception |
Error in data provided to SQL statement. More... | |
struct | pqxx::integrity_constraint_violation |
struct | pqxx::restrict_violation |
struct | pqxx::not_null_violation |
struct | pqxx::foreign_key_violation |
struct | pqxx::unique_violation |
struct | pqxx::check_violation |
struct | pqxx::invalid_cursor_state |
struct | pqxx::invalid_sql_statement_name |
struct | pqxx::invalid_cursor_name |
struct | pqxx::syntax_error |
struct | pqxx::undefined_column |
struct | pqxx::undefined_function |
struct | pqxx::undefined_table |
struct | pqxx::insufficient_privilege |
struct | pqxx::insufficient_resources |
Resource shortage on the server. More... | |
struct | pqxx::disk_full |
struct | pqxx::out_of_memory |
struct | pqxx::too_many_connections |
struct | pqxx::plpgsql_error |
PL/pgSQL error. More... | |
struct | pqxx::plpgsql_raise |
Exception raised in PL/pgSQL procedure. More... | |
struct | pqxx::plpgsql_no_data_found |
struct | pqxx::plpgsql_too_many_rows |
These exception classes follow, roughly, the two-level hierarchy defined by the PostgreSQL SQLSTATE error codes (see Appendix A of the PostgreSQL documentation corresponding to your server version). This is not a complete mapping though. There are other differences as well, e.g. the error code for statement_completion_unknown
has a separate status in libpqxx as in_doubt_error, and too_many_connections
is classified as a broken_connection
rather than a subtype of insufficient_resources
.
struct pqxx::failure |
Run-time failure encountered by libpqxx, similar to std::runtime_error.
Public Member Functions | |
failure (std::string const &) | |
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explicit |
Implementation of libpqxx exception classes.
Copyright (c) 2000-2025, Jeroen T. Vermeulen.
See COPYING for copyright license. If you did not receive a file called COPYING with this source code, please notify the distributor of this mistake, or contact the author.
struct pqxx::broken_connection |
Exception class for lost or failed backend connection.
If you're working on a Unix-like system, see the manual page for signal
(2) on how to deal with SIGPIPE. The easiest way to make this signal harmless is to make your program ignore it:
Public Member Functions | |
broken_connection (std::string const &) | |
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failure (std::string const &) | |
struct pqxx::protocol_violation |
Exception class for micommunication with the server.
This happens when the conversation between libpq and the server gets messed up. There aren't many situations where this happens, but one known instance is when you call a parameterised or prepared statement with th ewrong number of parameters.
So even though this is a broken_connection
, it signals that retrying is not likely to make the problem go away.
Public Member Functions | |
protocol_violation (std::string const &) | |
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broken_connection (std::string const &) | |
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failure (std::string const &) | |
struct pqxx::variable_set_to_null |
The caller attempted to set a variable to null, which is not allowed.
Public Member Functions | |
variable_set_to_null (std::string const &) | |
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failure (std::string const &) | |
class pqxx::sql_error |
Exception class for failed queries.
Carries, in addition to a regular error message, a copy of the failed query and (if available) the SQLSTATE value accompanying the error.
Public Member Functions | |
sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::in_doubt_error |
"Help, I don't know whether transaction was committed successfully!"
Exception that might be thrown in rare cases where the connection to the database is lost while finishing a database transaction, and there's no way of telling whether it was actually executed by the backend. In this case the database is left in an indeterminate (but consistent) state, and only manual inspection will tell which is the case.
Public Member Functions | |
in_doubt_error (std::string const &) | |
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failure (std::string const &) | |
struct pqxx::transaction_rollback |
The backend saw itself forced to roll back the ongoing transaction.
Public Member Functions | |
transaction_rollback (std::string const &whatarg, std::string const &q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::serialization_failure |
Transaction failed to serialize. Please retry it.
Can only happen at transaction isolation levels REPEATABLE READ and SERIALIZABLE.
The current transaction cannot be committed without violating the guarantees made by its isolation level. This is the effect of a conflict with another ongoing transaction. The transaction may still succeed if you try to perform it again.
Public Member Functions | |
serialization_failure (std::string const &whatarg, std::string const &q, char const sqlstate[]=nullptr) | |
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transaction_rollback (std::string const &whatarg, std::string const &q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::statement_completion_unknown |
We can't tell whether our last statement succeeded.
Public Member Functions | |
statement_completion_unknown (std::string const &whatarg, std::string const &q, char const sqlstate[]=nullptr) | |
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transaction_rollback (std::string const &whatarg, std::string const &q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::deadlock_detected |
The ongoing transaction has deadlocked. Retrying it may help.
Public Member Functions | |
deadlock_detected (std::string const &whatarg, std::string const &q, char const sqlstate[]=nullptr) | |
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transaction_rollback (std::string const &whatarg, std::string const &q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::internal_error |
Internal error in libpqxx library.
Public Member Functions | |
internal_error (std::string const &) | |
struct pqxx::usage_error |
Error in usage of libpqxx library, similar to std::logic_error.
Public Member Functions | |
usage_error (std::string const &) | |
struct pqxx::argument_error |
Invalid argument passed to libpqxx, similar to std::invalid_argument.
Public Member Functions | |
argument_error (std::string const &) | |
struct pqxx::conversion_error |
Value conversion failed, e.g. when converting "Hello" to int.
Public Member Functions | |
conversion_error (std::string const &) | |
struct pqxx::unexpected_null |
Could not convert null value: target type does not support null.
Public Member Functions | |
unexpected_null (std::string const &) | |
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conversion_error (std::string const &) | |
struct pqxx::conversion_overrun |
Could not convert value to string: not enough buffer space.
Public Member Functions | |
conversion_overrun (std::string const &) | |
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conversion_error (std::string const &) | |
struct pqxx::range_error |
Something is out of range, similar to std::out_of_range.
Public Member Functions | |
range_error (std::string const &) | |
struct pqxx::unexpected_rows |
Query returned an unexpected number of rows.
Public Member Functions | |
unexpected_rows (std::string const &msg) | |
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range_error (std::string const &) | |
struct pqxx::feature_not_supported |
Database feature not supported in current setup.
Public Member Functions | |
feature_not_supported (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::data_exception |
Error in data provided to SQL statement.
Public Member Functions | |
data_exception (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::integrity_constraint_violation |
Public Member Functions | |
integrity_constraint_violation (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::restrict_violation |
Public Member Functions | |
restrict_violation (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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integrity_constraint_violation (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::not_null_violation |
Public Member Functions | |
not_null_violation (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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integrity_constraint_violation (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::foreign_key_violation |
Public Member Functions | |
foreign_key_violation (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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integrity_constraint_violation (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::unique_violation |
Public Member Functions | |
unique_violation (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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integrity_constraint_violation (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::check_violation |
Public Member Functions | |
check_violation (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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integrity_constraint_violation (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::invalid_cursor_state |
Public Member Functions | |
invalid_cursor_state (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::invalid_sql_statement_name |
Public Member Functions | |
invalid_sql_statement_name (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::invalid_cursor_name |
Public Member Functions | |
invalid_cursor_name (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::syntax_error |
Public Member Functions | |
syntax_error (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr, int pos=-1) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
Public Attributes | |
int const | error_position |
Approximate position in string where error occurred, or -1 if unknown. | |
struct pqxx::undefined_column |
Public Member Functions | |
undefined_column (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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syntax_error (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr, int pos=-1) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
Additional Inherited Members | |
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int const | error_position |
Approximate position in string where error occurred, or -1 if unknown. | |
struct pqxx::undefined_function |
Public Member Functions | |
undefined_function (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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syntax_error (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr, int pos=-1) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
Additional Inherited Members | |
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int const | error_position |
Approximate position in string where error occurred, or -1 if unknown. | |
struct pqxx::undefined_table |
Public Member Functions | |
undefined_table (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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syntax_error (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr, int pos=-1) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
Additional Inherited Members | |
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int const | error_position |
Approximate position in string where error occurred, or -1 if unknown. | |
struct pqxx::insufficient_privilege |
Public Member Functions | |
insufficient_privilege (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::insufficient_resources |
Resource shortage on the server.
Public Member Functions | |
insufficient_resources (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::disk_full |
Public Member Functions | |
disk_full (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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insufficient_resources (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::out_of_memory |
Public Member Functions | |
out_of_memory (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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insufficient_resources (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::too_many_connections |
Public Member Functions | |
too_many_connections (std::string const &err) | |
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broken_connection (std::string const &) | |
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failure (std::string const &) | |
struct pqxx::plpgsql_error |
PL/pgSQL error.
Exceptions derived from this class are errors from PL/pgSQL procedures.
Public Member Functions | |
plpgsql_error (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::plpgsql_raise |
Exception raised in PL/pgSQL procedure.
Public Member Functions | |
plpgsql_raise (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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plpgsql_error (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::plpgsql_no_data_found |
Public Member Functions | |
plpgsql_no_data_found (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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plpgsql_error (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |
struct pqxx::plpgsql_too_many_rows |
Public Member Functions | |
plpgsql_too_many_rows (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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plpgsql_error (std::string const &err, std::string const &Q="", char const sqlstate[]=nullptr) | |
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sql_error (std::string const &whatarg="", std::string Q="", char const *sqlstate=nullptr) | |
PQXX_PURE std::string const & | query () const noexcept |
The query whose execution triggered the exception. | |
PQXX_PURE std::string const & | sqlstate () const noexcept |
SQLSTATE error code if known, or empty string otherwise. | |
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failure (std::string const &) | |