我们在操作数据库的时候，我们总会遇到很多错误。下面整理了一下常见的错误。
错误1
FATAL: connection limit exceeded for non-superusers
原因：非超级用户的连接数（max_connections - superuser_reserved_connections）超过了设定值
解决办法：增加max_connections设定值，但如果增加了过多的话，数据库负担太大还容易产生内存错误。可以记住pg-pool等工具来辅助解决。
错误2
FATAL: sorry, too many clients already
原因：数据库服务器的连接数超过了max_connections设定值。
解决办法：和错误1解决办法类似。
错误3
LOG: checkpoints are occurring too frequently
原因：checkpoint处理正频繁发生。
解决办法：增加checkpoint_segments的值。
错误4
LOG: archive command failed with exit code (X)
原因：archive_command 失败了。
解决办法：因为有可能是硬盘没空间了，所以可以把数据库的log删除一些。
错误5
LOG: number of page slots needed (X) exceeds max_fsm_pages (Y)
原因：max_fsm_pages不足了。
解决办法：增加max_fsm_pages的同时进行 VACUUM FULL。
错误6
ERROR: current transaction is aborted, commands ignored until end of transaction blockp
原因：数据库操作时，前一次操作中已经发生过错误了。
错误7
ERROR: operator does not exist: character = integer
原因：PostgreSQL8.3以后，取消了默认类型转换。因此需要使比较的类型保持一致。可以看cast函数。
附错误code
| Error Code | Meaning | Condition Name |
|---|---|---|
| Class 00 — Successful Completion | ||
| 00000 | SUCCESSFUL COMPLETION | successful_completion |
| Class 01 — Warning | ||
| 01000 | WARNING | warning |
| 0100C | DYNAMIC RESULT SETS RETURNED | dynamic_result_sets_returned |
| 01008 | IMPLICIT ZERO BIT PADDING | implicit_zero_bit_padding |
| 01003 | NULL VALUE ELIMINATED IN SET FUNCTION | null_value_eliminated_in_set_function |
| 01007 | PRIVILEGE NOT GRANTED | privilege_not_granted |
| 01006 | PRIVILEGE NOT REVOKED | privilege_not_revoked |
| 01004 | STRING DATA RIGHT TRUNCATION | string_data_right_truncation |
| 01P01 | DEPRECATED FEATURE | deprecated_feature |
| Class 02 — No Data (this is also a warning class per the SQL standard) | ||
| 02000 | NO DATA | no_data |
| 02001 | NO ADDITIONAL DYNAMIC RESULT SETS RETURNED | no_additional_dynamic_result_sets_returned |
| Class 03 — SQL Statement Not Yet Complete | ||
| 03000 | SQL STATEMENT NOT YET COMPLETE | sql_statement_not_yet_complete |
| Class 08 — Connection Exception | ||
| 08000 | CONNECTION EXCEPTION | connection_exception |
| 08003 | CONNECTION DOES NOT EXIST | connection_does_not_exist |
| 08006 | CONNECTION FAILURE | connection_failure |
| 08001 | SQLCLIENT UNABLE TO ESTABLISH SQLCONNECTION | sqlclient_unable_to_establish_sqlconnection |
| 08004 | SQLSERVER REJECTED ESTABLISHMENT OF SQLCONNECTION | sqlserver_rejected_establishment_of_sqlconnection |
| 08007 | TRANSACTION RESOLUTION UNKNOWN | transaction_resolution_unknown |
| 08P01 | PROTOCOL VIOLATION | protocol_violation |
| Class 09 — Triggered Action Exception | ||
| 09000 | TRIGGERED ACTION EXCEPTION | triggered_action_exception |
| Class 0A — Feature Not Supported | ||
| 0A000 | FEATURE NOT SUPPORTED | feature_not_supported |
| Class 0B — Invalid Transaction Initiation | ||
| 0B000 | INVALID TRANSACTION INITIATION | invalid_transaction_initiation |
| Class 0F — Locator Exception | ||
| 0F000 | LOCATOR EXCEPTION | locator_exception |
| 0F001 | INVALID LOCATOR SPECIFICATION | invalid_locator_specification |
| Class 0L — Invalid Grantor | ||
| 0L000 | INVALID GRANTOR | invalid_grantor |
| 0LP01 | INVALID GRANT OPERATION | invalid_grant_operation |
| Class 0P — Invalid Role Specification | ||
| 0P000 | INVALID ROLE SPECIFICATION | invalid_role_specification |
| Class 20 — Case Not Found | ||
| 20000 | CASE NOT FOUND | case_not_found |
| Class 21 — Cardinality Violation | ||
| 21000 | CARDINALITY VIOLATION | cardinality_violation |
| Class 22 — Data Exception | ||
| 22000 | DATA EXCEPTION | data_exception |
| 2202E | ARRAY SUBSCRIPT ERROR | array_subscript_error |
| 22021 | CHARACTER NOT IN REPERTOIRE | character_not_in_repertoire |
| 22008 | DATETIME FIELD OVERFLOW | datetime_field_overflow |
| 22012 | DIVISION BY ZERO | division_by_zero |
| 22005 | ERROR IN ASSIGNMENT | error_in_assignment |
| 2200B | ESCAPE CHARACTER CONFLICT | escape_character_conflict |
| 22022 | INDICATOR OVERFLOW | indicator_overflow |
| 22015 | INTERVAL FIELD OVERFLOW | interval_field_overflow |
| 2201E | INVALID ARGUMENT FOR LOGARITHM | invalid_argument_for_logarithm |
| 22014 | INVALID ARGUMENT FOR NTILE FUNCTION | invalid_argument_for_ntile_function |
| 22016 | INVALID ARGUMENT FOR NTH_VALUE FUNCTION | invalid_argument_for_nth_value_function |
| 2201F | INVALID ARGUMENT FOR POWER FUNCTION | invalid_argument_for_power_function |
| 2201G | INVALID ARGUMENT FOR WIDTH BUCKET FUNCTION | invalid_argument_for_width_bucket_function |
| 22018 | INVALID CHARACTER VALUE FOR CAST | invalid_character_value_for_cast |
| 22007 | INVALID DATETIME FORMAT | invalid_datetime_format |
| 22019 | INVALID ESCAPE CHARACTER | invalid_escape_character |
| 2200D | INVALID ESCAPE OCTET | invalid_escape_octet |
| 22025 | INVALID ESCAPE SEQUENCE | invalid_escape_sequence |
| 22P06 | NONSTANDARD USE OF ESCAPE CHARACTER | nonstandard_use_of_escape_character |
| 22010 | INVALID INDICATOR PARAMETER VALUE | invalid_indicator_parameter_value |
| 22023 | INVALID PARAMETER VALUE | invalid_parameter_value |
| 2201B | INVALID REGULAR EXPRESSION | invalid_regular_expression |
| 2201W | INVALID ROW COUNT IN LIMIT CLAUSE | invalid_row_count_in_limit_clause |
| 2201X | INVALID ROW COUNT IN RESULT OFFSET CLAUSE | invalid_row_count_in_result_offset_clause |
| 22009 | INVALID TIME ZONE DISPLACEMENT VALUE | invalid_time_zone_displacement_value |
| 2200C | INVALID USE OF ESCAPE CHARACTER | invalid_use_of_escape_character |
| 2200G | MOST SPECIFIC TYPE MISMATCH | most_specific_type_mismatch |
| 22004 | NULL VALUE NOT ALLOWED | null_value_not_allowed |
| 22002 | NULL VALUE NO INDICATOR PARAMETER | null_value_no_indicator_parameter |
| 22003 | NUMERIC VALUE OUT OF RANGE | numeric_value_out_of_range |
| 22026 | STRING DATA LENGTH MISMATCH | string_data_length_mismatch |
| 22001 | STRING DATA RIGHT TRUNCATION | string_data_right_truncation |
| 22011 | SUBSTRING ERROR | substring_error |
| 22027 | TRIM ERROR | trim_error |
| 22024 | UNTERMINATED C STRING | unterminated_c_string |
| 2200F | ZERO LENGTH CHARACTER STRING | zero_length_character_string |
| 22P01 | FLOATING POINT EXCEPTION | floating_point_exception |
| 22P02 | INVALID TEXT REPRESENTATION | invalid_text_representation |
| 22P03 | INVALID BINARY REPRESENTATION | invalid_binary_representation |
| 22P04 | BAD COPY FILE FORMAT | bad_copy_file_format |
| 22P05 | UNTRANSLATABLE CHARACTER | untranslatable_character |
| 2200L | NOT AN XML DOCUMENT | not_an_xml_document |
| 2200M | INVALID XML DOCUMENT | invalid_xml_document |
| 2200N | INVALID XML CONTENT | invalid_xml_content |
| 2200S | INVALID XML COMMENT | invalid_xml_comment |
| 2200T | INVALID XML PROCESSING INSTRUCTION | invalid_xml_processing_instruction |
| Class 23 — Integrity Constraint Violation | ||
| 23000 | INTEGRITY CONSTRAINT VIOLATION | integrity_constraint_violation |
| 23001 | RESTRICT VIOLATION | restrict_violation |
| 23502 | NOT NULL VIOLATION | not_null_violation |
| 23503 | FOREIGN KEY VIOLATION | foreign_key_violation |
| 23505 | UNIQUE VIOLATION | unique_violation |
| 23514 | CHECK VIOLATION | check_violation |
| Class 24 — Invalid Cursor State | ||
| 24000 | INVALID CURSOR STATE | invalid_cursor_state |
| Class 25 — Invalid Transaction State | ||
| 25000 | INVALID TRANSACTION STATE | invalid_transaction_state |
| 25001 | ACTIVE SQL TRANSACTION | active_sql_transaction |
| 25002 | BRANCH TRANSACTION ALREADY ACTIVE | branch_transaction_already_active |
| 25008 | HELD CURSOR REQUIRES SAME ISOLATION LEVEL | held_cursor_requires_same_isolation_level |
| 25003 | INAPPROPRIATE ACCESS MODE FOR BRANCH TRANSACTION | inappropriate_access_mode_for_branch_transaction |
| 25004 | INAPPROPRIATE ISOLATION LEVEL FOR BRANCH TRANSACTION | inappropriate_isolation_level_for_branch_transaction |
| 25005 | NO ACTIVE SQL TRANSACTION FOR BRANCH TRANSACTION | no_active_sql_transaction_for_branch_transaction |
| 25006 | READ ONLY SQL TRANSACTION | read_only_sql_transaction |
| 25007 | SCHEMA AND DATA STATEMENT MIXING NOT SUPPORTED | schema_and_data_statement_mixing_not_supported |
| 25P01 | NO ACTIVE SQL TRANSACTION | no_active_sql_transaction |
| 25P02 | IN FAILED SQL TRANSACTION | in_failed_sql_transaction |
| Class 26 — Invalid SQL Statement Name | ||
| 26000 | INVALID SQL STATEMENT NAME | invalid_sql_statement_name |
| Class 27 — Triggered Data Change Violation | ||
| 27000 | TRIGGERED DATA CHANGE VIOLATION | triggered_data_change_violation |
| Class 28 — Invalid Authorization Specification | ||
| 28000 | INVALID AUTHORIZATION SPECIFICATION | invalid_authorization_specification |
| Class 2B — Dependent Privilege Descriptors Still Exist | ||
| 2B000 | DEPENDENT PRIVILEGE DESCRIPTORS STILL EXIST | dependent_privilege_descriptors_still_exist |
| 2BP01 | DEPENDENT OBJECTS STILL EXIST | dependent_objects_still_exist |
| Class 2D — Invalid Transaction Termination | ||
| 2D000 | INVALID TRANSACTION TERMINATION | invalid_transaction_termination |
| Class 2F — SQL Routine Exception | ||
| 2F000 | SQL ROUTINE EXCEPTION | sql_routine_exception |
| 2F005 | FUNCTION EXECUTED NO RETURN STATEMENT | function_executed_no_return_statement |
| 2F002 | MODIFYING SQL DATA NOT PERMITTED | modifying_sql_data_not_permitted |
| 2F003 | PROHIBITED SQL STATEMENT ATTEMPTED | prohibited_sql_statement_attempted |
| 2F004 | READING SQL DATA NOT PERMITTED | reading_sql_data_not_permitted |
| Class 34 — Invalid Cursor Name | ||
| 34000 | INVALID CURSOR NAME | invalid_cursor_name |
| Class 38 — External Routine Exception | ||
| 38000 | EXTERNAL ROUTINE EXCEPTION | external_routine_exception |
| 38001 | CONTAINING SQL NOT PERMITTED | containing_sql_not_permitted |
| 38002 | MODIFYING SQL DATA NOT PERMITTED | modifying_sql_data_not_permitted |
| 38003 | PROHIBITED SQL STATEMENT ATTEMPTED | prohibited_sql_statement_attempted |
| 38004 | READING SQL DATA NOT PERMITTED | reading_sql_data_not_permitted |
| Class 39 — External Routine Invocation Exception | ||
| 39000 | EXTERNAL ROUTINE INVOCATION EXCEPTION | external_routine_invocation_exception |
| 39001 | INVALID SQLSTATE RETURNED | invalid_sqlstate_returned |
| 39004 | NULL VALUE NOT ALLOWED | null_value_not_allowed |
| 39P01 | TRIGGER PROTOCOL VIOLATED | trigger_protocol_violated |
| 39P02 | SRF PROTOCOL VIOLATED | srf_protocol_violated |
| Class 3B — Savepoint Exception | ||
| 3B000 | SAVEPOINT EXCEPTION | savepoint_exception |
| 3B001 | INVALID SAVEPOINT SPECIFICATION | invalid_savepoint_specification |
| Class 3D — Invalid Catalog Name | ||
| 3D000 | INVALID CATALOG NAME | invalid_catalog_name |
| Class 3F — Invalid Schema Name | ||
| 3F000 | INVALID SCHEMA NAME | invalid_schema_name |
| Class 40 — Transaction Rollback | ||
| 40000 | TRANSACTION ROLLBACK | transaction_rollback |
| 40002 | TRANSACTION INTEGRITY CONSTRAINT VIOLATION | transaction_integrity_constraint_violation |
| 40001 | SERIALIZATION FAILURE | serialization_failure |
| 40003 | STATEMENT COMPLETION UNKNOWN | statement_completion_unknown |
| 40P01 | DEADLOCK DETECTED | deadlock_detected |
| Class 42 — Syntax Error or Access Rule Violation | ||
| 42000 | SYNTAX ERROR OR ACCESS RULE VIOLATION | syntax_error_or_access_rule_violation |
| 42601 | SYNTAX ERROR | syntax_error |
| 42501 | INSUFFICIENT PRIVILEGE | insufficient_privilege |
| 42846 | CANNOT COERCE | cannot_coerce |
| 42803 | GROUPING ERROR | grouping_error |
| 42P20 | WINDOWING ERROR | windowing_error |
| 42P19 | INVALID RECURSION | invalid_recursion |
| 42830 | INVALID FOREIGN KEY | invalid_foreign_key |
| 42602 | INVALID NAME | invalid_name |
| 42622 | NAME TOO LONG | name_too_long |
| 42939 | RESERVED NAME | reserved_name |
| 42804 | DATATYPE MISMATCH | datatype_mismatch |
| 42P18 | INDETERMINATE DATATYPE | indeterminate_datatype |
| 42809 | WRONG OBJECT TYPE | wrong_object_type |
| 42703 | UNDEFINED COLUMN | undefined_column |
| 42883 | UNDEFINED FUNCTION | undefined_function |
| 42P01 | UNDEFINED TABLE | undefined_table |
| 42P02 | UNDEFINED PARAMETER | undefined_parameter |
| 42704 | UNDEFINED OBJECT | undefined_object |
| 42701 | DUPLICATE COLUMN | duplicate_column |
| 42P03 | DUPLICATE CURSOR | duplicate_cursor |
| 42P04 | DUPLICATE DATABASE | duplicate_database |
| 42723 | DUPLICATE FUNCTION | duplicate_function |
| 42P05 | DUPLICATE PREPARED STATEMENT | duplicate_prepared_statement |
| 42P06 | DUPLICATE SCHEMA | duplicate_schema |
| 42P07 | DUPLICATE TABLE | duplicate_table |
| 42712 | DUPLICATE ALIAS | duplicate_alias |
| 42710 | DUPLICATE OBJECT | duplicate_object |
| 42702 | AMBIGUOUS COLUMN | ambiguous_column |
| 42725 | AMBIGUOUS FUNCTION | ambiguous_function |
| 42P08 | AMBIGUOUS PARAMETER | ambiguous_parameter |
| 42P09 | AMBIGUOUS ALIAS | ambiguous_alias |
| 42P10 | INVALID COLUMN REFERENCE | invalid_column_reference |
| 42611 | INVALID COLUMN DEFINITION | invalid_column_definition |
| 42P11 | INVALID CURSOR DEFINITION | invalid_cursor_definition |
| 42P12 | INVALID DATABASE DEFINITION | invalid_database_definition |
| 42P13 | INVALID FUNCTION DEFINITION | invalid_function_definition |
| 42P14 | INVALID PREPARED STATEMENT DEFINITION | invalid_prepared_statement_definition |
| 42P15 | INVALID SCHEMA DEFINITION | invalid_schema_definition |
| 42P16 | INVALID TABLE DEFINITION | invalid_table_definition |
| 42P17 | INVALID OBJECT DEFINITION | invalid_object_definition |
| Class 44 — WITH CHECK OPTION Violation | ||
| 44000 | WITH CHECK OPTION VIOLATION | with_check_option_violation |
| Class 53 — Insufficient Resources | ||
| 53000 | INSUFFICIENT RESOURCES | insufficient_resources |
| 53100 | DISK FULL | disk_full |
| 53200 | OUT OF MEMORY | out_of_memory |
| 53300 | TOO MANY CONNECTIONS | too_many_connections |
| Class 54 — Program Limit Exceeded | ||
| 54000 | PROGRAM LIMIT EXCEEDED | program_limit_exceeded |
| 54001 | STATEMENT TOO COMPLEX | statement_too_complex |
| 54011 | TOO MANY COLUMNS | too_many_columns |
| 54023 | TOO MANY ARGUMENTS | too_many_arguments |
| Class 55 — Object Not In Prerequisite State | ||
| 55000 | OBJECT NOT IN PREREQUISITE STATE | object_not_in_prerequisite_state |
| 55006 | OBJECT IN USE | object_in_use |
| 55P02 | CANT CHANGE RUNTIME PARAM | cant_change_runtime_param |
| 55P03 | LOCK NOT AVAILABLE | lock_not_available |
| Class 57 — Operator Intervention | ||
| 57000 | OPERATOR INTERVENTION | operator_intervention |
| 57014 | QUERY CANCELED | query_canceled |
| 57P01 | ADMIN SHUTDOWN | admin_shutdown |
| 57P02 | CRASH SHUTDOWN | crash_shutdown |
| 57P03 | CANNOT CONNECT NOW | cannot_connect_now |
| Class 58 — System Error (errors external to PostgreSQL itself) | ||
| 58030 | IO ERROR | io_error |
| 58P01 | UNDEFINED FILE | undefined_file |
| 58P02 | DUPLICATE FILE | duplicate_file |
| Class F0 — Configuration File Error | ||
| F0000 | CONFIG FILE ERROR | config_file_error |
| F0001 | LOCK FILE EXISTS | lock_file_exists |
| Class P0 — PL/pgSQL Error | ||
| P0000 | PLPGSQL ERROR | plpgsql_error |
| P0001 | RAISE EXCEPTION | raise_exception |
| P0002 | NO DATA FOUND | no_data_found |
| P0003 | TOO MANY ROWS | too_many_rows |
| Class XX — Internal Error | ||
| XX000 | INTERNAL ERROR | internal_error |
| XX001 | DATA CORRUPTED | data_corrupted |
| XX002 | INDEX CORRUPTED | index_corrupted |