OceanBase

A unified distributed database ready for your transactional, analytical, and AI workloads.

Product Overview

DEPLOY YOUR WAY

OceanBase Cloud

The best way to deploy and scale OceanBase

OceanBase Enterprise

Run and manage OceanBase on your infra

TRY OPEN SOURCE

OceanBase Community Edition

The free, open-source distributed database

OceanBase seekdb

Open source AI native search database

Customer Stories

Real-world success stories from enterprises across diverse industries.

View All

BY USE CASES

Mission-Critical Transactions

Global & Multicloud Application

Elastic Scaling for Peak Traffic

Real-time Analytics

Active Geo-redundancy

Database Consolidation

Comprehensive knowledge hub for OceanBase.

Blog

Live Demos

Training & Certification

Documentation

Official technical guides, tutorials, API references, and manuals for all OceanBase products.

View All

PRODUCTS

OceanBase Cloud

OceanBase Database

Tools Connectors and Middleware

QUICK START

OceanBase Cloud OceanBase Database

BEST PRACTICES

Practical guides for utilizing OceanBase more effectively and conveniently

Learn more about OceanBase – our company, partnerships, and trust and security initiatives.

About OceanBase

Partner

Trust Center

OceanBase Database Proxy

V4.2.2

What is ODP?
Installation and deployment
- Overview
- Use OBD to deploy ODP
- Deploy ODP by using OCP
- Deploy ODP by using the CLI
- Deployment modes
Basic operations
Configuration parameter
- View and modify parameters
- Parameter summary
- Parameters that take effect dynamically
  - binlog_service_ip
  - cache_cleaner_clean_interval
  - check_tenant_locality_change
  - client_max_connections
  - client_max_memory_size
  - client_sock_option_flag_out
  - client_tcp_keepcnt
  - client_tcp_keepidle
  - client_tcp_keepintvl
  - client_tcp_user_timeout
  - cluster_count_high_water_mark
  - cluster_expire_time
  - config_server_refresh_interval
  - congestion_fail_window
  - congestion_failure_threshold
  - congestion_retry_interval
  - connection_diagnosis_option
  - connect_observer_max_retries
  - current_local_config_version
  - default_buffer_water_mark
  - default_inactivity_timeout
  - delay_exit_time
  - delay_update_entry_interval
  - detect_server_timeout
  - digest_sql_length
  - enable_abort_conn_info
  - enable_async_log
  - enable_async_pull_location_cache
  - enable_bad_route_reject
  - enable_binlog_service
  - enable_cached_server
  - enable_causal_order_read
  - enable_client_connection_lru_disconnect
  - enable_client_ip_checkout
  - enable_client_ssl
  - enable_cloud_full_username
  - enable_cluster_checkout
  - enable_compression_protocol
  - enable_congestion
  - enable_connection_diagnosis
  - enable_extra_prometheus_metric
  - enable_flow_control
  - enable_full_username
  - enable_get_rslist_remote
  - enable_index_route
  - enable_monitor_stat
  - enable_ob_protocol_v2
  - enable_ob_protocol_v2_with_client
  - enable_partition_table_route
  - enable_performance_mode
  - enable_pl_route
  - enable_primary_zone
  - enable_prometheus
  - enable_proxy_scramble
  - enable_qa_mode
  - enable_qos
  - enable_read_write_split
  - enable_report_session_stats
  - enable_reroute
  - enable_sequence_prefetch
  - enable_server_ssl
  - enable_sharding
  - enable_standby
  - enable_stat
  - enable_strict_stat_time
  - enable_sync_all_stats
  - enable_syslog_file_compress
  - enable_trace
  - enable_trace_stats
  - enable_trans_detail_stats
  - enable_transaction_internal_routing
  - enable_transaction_split
  - enable_weak_reroute
  - enable_xa_route
  - fetch_proxy_bin_random_time
  - fetch_proxy_bin_timeout
  - flow_consumer_reenable_threshold
  - flow_event_queue_threshold
  - flow_high_water_mark
  - flow_low_water_mark
  - hot_upgrade_exit_timeout
  - hot_upgrade_failure_retries
  - hot_upgrade_rollback_timeout
  - idc_list_refresh_interval
  - ignore_local_config
  - internal_cmd_mem_limited
  - ldg_info_refresh_interval
  - log_cleanup_interval
  - log_dir_size_threshold
  - log_file_percentage
  - long_async_task_timeout
  - max_log_file_size
  - max_syslog_file_count
  - max_syslog_file_time
  - metadb_server_state_refresh_interval
  - min_congested_connect_timeout
  - min_keep_congestion_interval
  - monitor_cost_ms_unit
  - monitor_item_limit
  - monitor_item_max_idle_period
  - monitor_log_level
  - monitor_stat_dump_interval
  - monitor_stat_high_threshold
  - monitor_stat_low_threshold
  - monitor_stat_middle_threshold
  - mysql_version
  - need_convert_vip_to_tname
  - net_config_poll_timeout
  - normal_pl_update_threshold
  - ob_max_read_stale_time
  - obproxy_force_parallel_query_dop
  - obproxy_read_consistency
  - obproxy_read_only
  - obproxy_sys_password
  - observer_query_timeout_delta
  - observer_sys_password
  - observer_sys_password1
  - partition_location_expire_relative_time
  - prometheus_sync_interval
  - proxy_hot_upgrade_check_interval
  - proxy_idc_name
  - proxy_info_check_interval
  - proxy_local_cmd
  - proxy_mem_limited
  - proxy_primary_zone_name
  - proxy_route_policy
  - proxy_tenant_name
  - qa_mode_mock_public_cloud_slb_addr
  - qos_stat_clean_interval
  - qos_stat_item_limit
  - query_digest_time_threshold
  - read_stale_retry_interval
  - refresh_idc_list
  - refresh_json_config
  - refresh_rslist
  - request_buffer_length
  - route_diagnosis_level
  - routing_cache_mem_limited
  - sequence_entry_expire_time
  - sequence_fail_retry_count
  - sequence_prefetch_threshold
  - server_detect_fail_threshold
  - server_detect_mode
  - server_detect_refresh_interval
  - server_routing_mode
  - server_state_refresh_interval
  - server_tcp_init_cwnd
  - server_tcp_keepcnt
  - server_tcp_keepidle
  - server_tcp_keepintvl
  - server_tcp_user_timeout
  - short_async_task_timeout
  - skip_proxy_sys_private_check
  - skip_proxyro_check
  - slow_proxy_process_time_threshold
  - slow_query_time_threshold
  - slow_transaction_time_threshold
  - sock_option_flag_out
  - sock_packet_mark_out
  - sock_packet_tos_out
  - sock_recv_buffer_size_out
  - sock_send_buffer_size_out
  - sql_table_cache_expire_relative_time
  - sql_table_cache_mem_limited
  - sqlaudit_mem_limited
  - ssl_attributes
  - stat_dump_interval
  - stat_table_sync_interval
  - syslog_level
  - target_db_server
  - tenant_location_valid_time
  - tunnel_request_size_threshold
  - username_separator
  - xflush_log_level
- Parameters that take effect after a restart
  - automatic_match_work_thread
  - block_thread_num
  - enable_cpu_isolate
  - enable_cpu_topology
  - enable_global_ps_cache
  - enable_strict_kernel_release
  - grpc_client_num
  - grpc_thread_num
  - ip_listen_mode
  - listen_port
  - local_bound_ip
  - local_bound_ipv6_ip
  - net_accept_threads
  - obproxy_config_server_url
  - prometheus_cost_ms_unit
  - prometheus_listen_port
  - rootservice_cluster_name
  - rootservice_list
  - shard_scan_thread_num
  - stack_size
  - task_thread_num
  - work_thread_num
Connection management
- Principles
- Session status synchronization
- Client session
- Server session
- Connection diagnostics
Data routing
- Factors affecting data routing
- ODP routing
- Intra-tenant routing
  - Overview
  - IP address-based routing
  - Partitioned table-based routing for strong-consistency reads
  - Global index table-based routing for strong-consistency reads
  - Replication table-based routing for strong-consistency reads
  - Primary zone-based routing for strong-consistency reads
  - Strategy-based routing
  - Distributed transaction routing
  - Rerouting
  - Forcible routing
- Read/Write separation
- Follower latency threshold
High availability mechanism
- Overview
- High availability of ODP services
- High availability of OceanBase Database
- High availability testing
Security and protocols
Operation and maintenance
- Troubleshooting
  - Troubleshooting logic
  - Monitoring logs
- Performance analysis
- Show Trace
- Routing diagnostics
  - Overview
  - Obtain diagnostic information
  - Diagnostic point troubleshooting
    - Overview
    - SQL_PARSE
    - ROUTE_INFO
    - LOCATION_CACHE_LOOKUP
    - ROUTINE_ENTRY_LOOKUP_DONE
    - FETCH_TABLE_RELATED_DATA
    - TABLE_ENTRY_LOOKUP_DONE
    - EXPR_PARSE
    - CALC_ROWID
    - RESOLVE_TOKEN
    - RESOLVE_EXPR
    - CALC_PARTITION_ID
    - PARTITION_ID_CALC_DONE
    - PARTITION_ENTRY_LOOKUP_DONE
    - ROUTE_POLICY
    - CONGESTION_CONTROL
    - RETRY
    - HANDLE_RESPONSE
  - Examples
Release Notes
- Versioning rules
- Enterprise Edition
  - V4.2
    - ODP Enterprise Edition V4.2.2
    - ODP Enterprise Edition V4.2.1
  - V4.1
    - ODP Enterprise Edition V4.1.0
  - V4.0
    - ODP Enterprise Edition V4.0.0
  - V3.2
    - ODP V3.2.11
    - ODP Enterprise Edition V3.2.3.5
- Community Edition
  - V4.2
    - ODP Community Edition V4.2.1
    - ODP Community Edition V4.2.0
  - V4.1
    - ODP Community Edition V4.1.0
  - V4.0
    - ODP Community Edition V4.0.0

Download PDF

Document Feedback

enable_causal_order_read

Last Updated：2026-04-14 09:41:35 Updated

enable_causal_order_read specifies whether OceanBase Database Proxy (ODP) selects a server by priority and synchronizes the security snapshot version as needed.

Attribute	Description
Parameter type	Boolean
Default value	True
Value range	`True`: ODP selects a server by priority and synchronizes the security snapshot version as needed. `False`: ODP randomly selects a server.

Previous topic

enable_cached_server

Last

Next topic

enable_client_connection_lru_disconnect