本文对不同数据库解释了异常类型的处理方法 。

背景说明

PolarDB O引擎不支持Oracle的异常类型,如果使用Oracle的异常类型会提示语法错误:
ERROR:  "utl_smtp.transient_error" is not a known exception

PolarDB O引擎中可以覆盖Oracle的异常类型,请根据PolarDB O引擎的异常处理方式进行改造。

解决方案

异常处理语法:
[ <<label>> ]
[ DECLARE
    declarations ]
BEGIN
    statements
EXCEPTION
    WHEN condition [ OR condition ... ] THEN
        handler_statements
    [ WHEN condition [ OR condition ... ] THEN
          handler_statements
      ... ]
END;
  • 如果没有发生异常,程序会正常执行所有的statements
  • 如果在statements内发生了一个异常,会支持跳转到EXCEPTION部分开始执行。系统会在WHEN列表中匹配第一个condition,如果没成功匹配,异常会继续向上抛。condition可以是附录中异常名称的任意一种。
说明 PolarDB O引擎支持的异常类型请见附录

示例

除零错误异常处理示例:
INSERT INTO mytab(firstname, lastname) VALUES('Tom', 'Jones');
BEGIN
    UPDATE mytab SET firstname = 'Joe' WHERE lastname = 'Jones';
    x := x + 1;
    y := x / 0;
EXCEPTION
    WHEN division_by_zero THEN
        RAISE NOTICE 'caught division_by_zero';
        RETURN x;
END;

附录

Error Code Condition Name
Class 00 — Successful Completion
00000 successful_completion
Class 01 — Warning
01000 warning
0100C dynamic_result_sets_returned
01008 implicit_zero_bit_padding
01003 null_value_eliminated_in_set_function
01007 privilege_not_granted
01006 privilege_not_revoked
01004 string_data_right_truncation
01P01 deprecated_feature
Class 02 — No Data (this is also a warning class per the SQL standard)
02000 no_data
02001 no_additional_dynamic_result_sets_returned
Class 03 — SQL Statement Not Yet Complete
03000 sql_statement_not_yet_complete
Class 08 — Connection Exception
08000 connection_exception
08003 connection_does_not_exist
08006 connection_failure
08001 sqlclient_unable_to_establish_sqlconnection
08004 sqlserver_rejected_establishment_of_sqlconnection
08007 transaction_resolution_unknown
08P01 protocol_violation
Class 09 — Triggered Action Exception
09000 triggered_action_exception
Class 0A — Feature Not Supported
0A000 feature_not_supported
Class 0B — Invalid Transaction Initiation
0B000 invalid_transaction_initiation
Class 0F — Locator Exception
0F000 locator_exception
0F001 invalid_locator_specification
Class 0L — Invalid Grantor
0L000 invalid_grantor
0LP01 invalid_grant_operation
Class 0P — Invalid Role Specification
0P000 invalid_role_specification
Class 0Z — Diagnostics Exception
0Z000 diagnostics_exception
0Z002 stacked_diagnostics_accessed_without_active_handler
Class 20 — Case Not Found
20000 case_not_found
Class 21 — Cardinality Violation
21000 cardinality_violation
Class 22 — Data Exception
22000 data_exception
2202E array_subscript_error
22021 character_not_in_repertoire
22008 datetime_field_overflow
22012 division_by_zero
22005 error_in_assignment
2200B escape_character_conflict
22022 indicator_overflow
22015 interval_field_overflow
2201E invalid_argument_for_logarithm
22014 invalid_argument_for_ntile_function
22016 invalid_argument_for_nth_value_function
2201F invalid_argument_for_power_function
2201G invalid_argument_for_width_bucket_function
22018 invalid_character_value_for_cast
22007 invalid_datetime_format
22019 invalid_escape_character
2200D invalid_escape_octet
22025 invalid_escape_sequence
22P06 nonstandard_use_of_escape_character
22010 invalid_indicator_parameter_value
22023 invalid_parameter_value
22013 invalid_preceding_or_following_size
2201B invalid_regular_expression
2201W invalid_row_count_in_limit_clause
2201X invalid_row_count_in_result_offset_clause
2202H invalid_tablesample_argument
2202G invalid_tablesample_repeat
22009 invalid_time_zone_displacement_value
2200C invalid_use_of_escape_character
2200G most_specific_type_mismatch
22004 null_value_not_allowed
22002 null_value_no_indicator_parameter
22003 numeric_value_out_of_range
2200H sequence_generator_limit_exceeded
22026 string_data_length_mismatch
22001 string_data_right_truncation
22011 substring_error
22027 trim_error
22024 unterminated_c_string
2200F zero_length_character_string
22P01 floating_point_exception
22P02 invalid_text_representation
22P03 invalid_binary_representation
22P04 bad_copy_file_format
22P05 untranslatable_character
2200L not_an_xml_document
2200M invalid_xml_document
2200N invalid_xml_content
2200S invalid_xml_comment
2200T invalid_xml_processing_instruction
Class 23 — Integrity Constraint Violation
23000 integrity_constraint_violation
23001 restrict_violation
23502 not_null_violation
23503 foreign_key_violation
23505 unique_violation
23514 check_violation
23P01 exclusion_violation
Class 24 — Invalid Cursor State
24000 invalid_cursor_state
Class 25 — Invalid Transaction State
25000 invalid_transaction_state
25001 active_sql_transaction
25002 branch_transaction_already_active
25008 held_cursor_requires_same_isolation_level
25003 inappropriate_access_mode_for_branch_transaction
25004 inappropriate_isolation_level_for_branch_transaction
25005 no_active_sql_transaction_for_branch_transaction
25006 read_only_sql_transaction
25007 schema_and_data_statement_mixing_not_supported
25P01 no_active_sql_transaction
25P02 in_failed_sql_transaction
25P03 idle_in_transaction_session_timeout
Class 26 — Invalid SQL Statement Name
26000 invalid_sql_statement_name
Class 27 — Triggered Data Change Violation
27000 triggered_data_change_violation
Class 28 — Invalid Authorization Specification
28000 invalid_authorization_specification
28P01 invalid_password
Class 2B — Dependent Privilege Descriptors Still Exist
2B000 dependent_privilege_descriptors_still_exist
2BP01 dependent_objects_still_exist
Class 2D — Invalid Transaction Termination
2D000 invalid_transaction_termination
Class 2F — SQL Routine Exception
2F000 sql_routine_exception
2F005 function_executed_no_return_statement
2F002 modifying_sql_data_not_permitted
2F003 prohibited_sql_statement_attempted
2F004 reading_sql_data_not_permitted
Class 34 — Invalid Cursor Name
34000 invalid_cursor_name
Class 38 — External Routine Exception
38000 external_routine_exception
38001 containing_sql_not_permitted
38002 modifying_sql_data_not_permitted
38003 prohibited_sql_statement_attempted
38004 reading_sql_data_not_permitted
Class 39 — External Routine Invocation Exception
39000 external_routine_invocation_exception
39001 invalid_sqlstate_returned
39004 null_value_not_allowed
39P01 trigger_protocol_violated
39P02 srf_protocol_violated
39P03 event_trigger_protocol_violated
Class 3B — Savepoint Exception
3B000 savepoint_exception
3B001 invalid_savepoint_specification
Class 3D — Invalid Catalog Name
3D000 invalid_catalog_name
Class 3F — Invalid Schema Name
3F000 invalid_schema_name
Class 40 — Transaction Rollback
40000 transaction_rollback
40002 transaction_integrity_constraint_violation
40001 serialization_failure
40003 statement_completion_unknown
40P01 deadlock_detected
Class 42 — Syntax Error or Access Rule Violation
42000 syntax_error_or_access_rule_violation
42601 syntax_error
42501 insufficient_privilege
42846 cannot_coerce
42803 grouping_error
42P20 windowing_error
42P19 invalid_recursion
42830 invalid_foreign_key
42602 invalid_name
42622 name_too_long
42939 reserved_name
42804 datatype_mismatch
42P18 indeterminate_datatype
42P21 collation_mismatch
42P22 indeterminate_collation
42809 wrong_object_type
428C9 generated_always
42703 undefined_column
42883 undefined_function
42P01 undefined_table
42P02 undefined_parameter
42704 undefined_object
42701 duplicate_column
42P03 duplicate_cursor
42P04 duplicate_database
42723 duplicate_function
42P05 duplicate_prepared_statement
42P06 duplicate_schema
42P07 duplicate_table
42712 duplicate_alias
42710 duplicate_object
42702 ambiguous_column
42725 ambiguous_function
42P08 ambiguous_parameter
42P09 ambiguous_alias
42P10 invalid_column_reference
42611 invalid_column_definition
42P11 invalid_cursor_definition
42P12 invalid_database_definition
42P13 invalid_function_definition
42P14 invalid_prepared_statement_definition
42P15 invalid_schema_definition
42P16 invalid_table_definition
42P17 invalid_object_definition
Class 44 — WITH CHECK OPTION Violation
44000 with_check_option_violation
Class 53 — Insufficient Resources
53000 insufficient_resources
53100 disk_full
53200 out_of_memory
53300 too_many_connections
53400 configuration_limit_exceeded
Class 54 — Program Limit Exceeded
54000 program_limit_exceeded
54001 statement_too_complex
54011 too_many_columns
54023 too_many_arguments
Class 55 — Object Not In Prerequisite State
55000 object_not_in_prerequisite_state
55006 object_in_use
55P02 cant_change_runtime_param
55P03 lock_not_available
Class 57 — Operator Intervention
57000 operator_intervention
57014 query_canceled
57P01 admin_shutdown
57P02 crash_shutdown
57P03 cannot_connect_now
57P04 database_dropped
Class 58 — System Error (errors external to PostgreSQL itself)
58000 system_error
58030 io_error
58P01 undefined_file
58P02 duplicate_file
Class 72 — Snapshot Failure
72000 snapshot_too_old
Class F0 — Configuration File Error
F0000 config_file_error
F0001 lock_file_exists
Class HV — Foreign Data Wrapper Error (SQL/MED)
HV000 fdw_error
HV005 fdw_column_name_not_found
HV002 fdw_dynamic_parameter_value_needed
HV010 fdw_function_sequence_error
HV021 fdw_inconsistent_descriptor_information
HV024 fdw_invalid_attribute_value
HV007 fdw_invalid_column_name
HV008 fdw_invalid_column_number
HV004 fdw_invalid_data_type
HV006 fdw_invalid_data_type_descriptors
HV091 fdw_invalid_descriptor_field_identifier
HV00B fdw_invalid_handle
HV00C fdw_invalid_option_index
HV00D fdw_invalid_option_name
HV090 fdw_invalid_string_length_or_buffer_length
HV00A fdw_invalid_string_format
HV009 fdw_invalid_use_of_null_pointer
HV014 fdw_too_many_handles
HV001 fdw_out_of_memory
HV00P fdw_no_schemas
HV00J fdw_option_name_not_found
HV00K fdw_reply_handle
HV00Q fdw_schema_not_found
HV00R fdw_table_not_found
HV00L fdw_unable_to_create_execution
HV00M fdw_unable_to_create_reply
HV00N fdw_unable_to_establish_connection
Class P0 — PL/pgSQL Error
P0000 plpgsql_error
P0001 raise_exception
P0002 no_data_found
P0003 too_many_rows
P0004 assert_failure
Class XX — Internal Error
XX000 internal_error
XX001 data_corrupted
XX002 index_corrupted