1"use strict";(globalThis.webpackChunkclougence_officialsite_new=globalThis.webpackChunkclougence_officialsite_new||[]).push([[13985],{36256(e,n,i){i.r(n),i.d(n,{assets:()=>l,contentTitle:()=>r,default:()=>h,frontMatter:()=>o,metadata:()=>t,toc:()=>c});var t=i(58200),s=i(74848),a=i(28453);const o={id:"oracle_clickhouse_sync",description:"Looking for the best ETL/data integration tool for Oracle to ClickHouse? This guide compares options and shows how to migrate and keep data in sync (schema, deletes, and verification).",title:"Best ETL Tool for Oracle to ClickHouse (Migration + Comparison)",date:new Date("2025-03-05T00:00:00.000Z"),authors:"juantu",tags:["tutorials"],image:"/img/blog/tutorials/oracle_clickhouse_sync.png"},r=void 0,l={authorsImageUrls:[void 0]},c=[{value:"Overview",id:"overview",level:2},{value:"Oracle to ClickHouse Migration / ETL Tool Comparison (How to Choose)",id:"oracle-to-clickhouse-migration--etl-tool-comparison-how-to-choose",level:2},{value:"Highlights",id:"highlights",level:2},{value:"ReplacingMergeTree Optimization",id:"replacingmergetree-optimization",level:3},{value:"Schema Migration",id:"schema-migration",level:3},{value:"Data Writing",id:"data-writing",level:3},{value:"DML Conversion",id:"dml-conversion",level:4},{value:"Data Version",id:"data-version",level:4},{value:"Procedure",id:"procedure",level:2},{value:"Step 1: Install BladePipe",id:"step-1-install-bladepipe",level:3},{value:"Step 2: Add DataSources",id:"step-2-add-datasources",level:3},{value:"Step 3: Create a DataJob",id:"step-3-create-a-datajob",level:3},{value:"Step 4: Verify the Data",id:"step-4-verify-the-data",level:3},{value:"FAQs",id:"faqs",level:2},{value:"Oracle to ClickHouse migration: what are the top 5 features to compare?",id:"oracle-to-clickhouse-migration-what-are-the-top-5-features-to-compare",level:3},{value:"Which data integration tool is best for Oracle to ClickHouse?",id:"which-data-integration-tool-is-best-for-oracle-to-clickhouse",level:3},{value:"Best ETL tool Oracle to ClickHouse: batch or real-time?",id:"best-etl-tool-oracle-to-clickhouse-batch-or-real-time",level:3},{value:"Do I need CDC for a one-time Oracle to ClickHouse migration?",id:"do-i-need-cdc-for-a-one-time-oracle-to-clickhouse-migration",level:3},{value:"How to avoid data drift in Oracle to ClickHouse pipelines?",id:"how-to-avoid-data-drift-in-oracle-to-clickhouse-pipelines",level:3},{value:"Can Oracle to ClickHouse tools support real-time data pipelines?",id:"can-oracle-to-clickhouse-tools-support-real-time-data-pipelines",level:3}];function d(e){const n={a:"a",admonition:"admonition",code:"code",h2:"h2",h3:"h3",h4:"h4",img:"img",li:"li",ol:"ol",p:"p",pre:"pre",strong:"strong",ul:"ul",...(0,a.R)(),...e.components};return(0,s.jsxs)(s.Fragment,{children:[(0,s.jsx)(n.h2,{id:"overview",children:"Overview"}),"\n",(0,s.jsxs)(n.p,{children:[(0,s.jsx)(n.a,{href:"/connector/clickhouse/",children:"ClickHouse"})," is an open-source column-oriented database management system. Its performance in real-time data processing can significantly enhance analytics and business insights. Moving data from ",(0,s.jsx)(n.a,{href:"/connector/oracle/",children:"Oracle"})," to ClickHouse can unlock fast OLAP queries without changing your existing OLTP system."]}),"\n",(0,s.jsxs)(n.p,{children:["If you're searching for ",(0,s.jsx)(n.strong,{children:"the best data integration tool to move data from Oracle DB to ClickHouse"}),", the right answer depends on whether you need a one-time migration, continuous sync (CDC), schema change handling, and how much operational burden you're willing to take on."]}),"\n",(0,s.jsx)(n.p,{children:"This guide includes:"}),"\n",(0,s.jsxs)(n.ul,{children:["\n",(0,s.jsxs)(n.li,{children:["A practical ",(0,s.jsx)(n.strong,{children:"Oracle to ClickHouse migration / ETL tool comparison"})," (what to look for)."]}),"\n",(0,s.jsxs)(n.li,{children:["A step-by-step tutorial to move data from Oracle to ClickHouse with ",(0,s.jsx)(n.a,{href:"https://www.bladepipe.com",children:"BladePipe"}),"."]}),"\n"]}),"\n",(0,s.jsx)(n.p,{children:"By default, BladePipe uses ReplacingMergeTree as the ClickHouse table engine. Key features include:"}),"\n",(0,s.jsxs)(n.ul,{children:["\n",(0,s.jsxs)(n.li,{children:["Add ",(0,s.jsx)(n.code,{children:"_sign"})," and ",(0,s.jsx)(n.code,{children:"_version"})," fields in ReplacingMergeTree table."]}),"\n",(0,s.jsx)(n.li,{children:"Support for DDL synchronization."}),"\n"]}),"\n",(0,s.jsx)(n.h2,{id:"oracle-to-clickhouse-migration--etl-tool-comparison-how-to-choose",children:"Oracle to ClickHouse Migration / ETL Tool Comparison (How to Choose)"}),"\n",(0,s.jsxs)(n.p,{children:['If your query is "',(0,s.jsx)(n.strong,{children:"which is the best data integration tool to move data from Oracle DB to ClickHouse?"}),'", start with these decision points:']}),"\n",(0,s.jsxs)(n.ul,{children:["\n",(0,s.jsxs)(n.li,{children:[(0,s.jsx)(n.strong,{children:"One-time migration vs continuous sync (CDC):"})," A one-time copy is simpler;
1 continuous sync requires log-based change capture, ordering, and recovery."]}),"\n",(0,s.jsxs)(n.li,{children:[(0,s.jsx)(n.strong,{children:"Deletes and updates correctness:"})," ClickHouse is append-optimized; make sure your approach handles UPDATE/DELETE semantics safely at scale."]}),"\n",(0,s.jsxs)(n.li,{children:[(0,s.jsx)(n.strong,{children:"Schema migration and DDL sync:"})," Oracle schema changes are common in real systems; a production pipeline needs a plan for DDL."]}),"\n",(0,s.jsxs)(n.li,{children:[(0,s.jsx)(n.strong,{children:"Operational burden:"})," DIY stacks can work, but you\u2019ll own retries, backpressure, alerting, and drift."]}),"\n",(0,s.jsxs)(n.li,{children:[(0,s.jsx)(n.strong,{children:"Verification and reconciliation:"})," You need a repeatable way to prove ClickHouse matches Oracle after initial load and during incremental sync."]}),"\n"]}),"\n",(0,s.jsx)(n.p,{children:"If you want a quick best tool shortcut:"}),"\n",(0,s.jsxs)(n.ul,{children:["\n",(0,s.jsxs)(n.li,{children:["Choose a managed/packaged data integration tool when you want ",(0,s.jsx)(n.strong,{children:"faster time-to-value"})," and less engineering/ops work."]}),"\n",(0,s.jsxs)(n.li,{children:["Choose a DIY stack when you need ",(0,s.jsx)(n.strong,{children:"full control"})," and can afford the engineering and maintenance cost."]}),"\n"]}),"\n",(0,s.jsxs)(n.p,{children:["If you want background on change-streaming patterns and reliability guarantees, see ",(0,s.jsx)(n.a,{href:"/blog/data_insights/change_data_capture_cdc",children:"Change Data Capture (CDC)"})," and ",(0,s.jsx)(n.a,{href:"/blog/data_insights/change_data_capture_use_cases",children:"CDC use cases"}),"."]}),"\n",(0,s.jsx)(n.h2,{id:"highlights",children:"Highlights"}),"\n",(0,s.jsx)(n.h3,{id:"replacingmergetree-optimization",children:"ReplacingMergeTree Optimization"}),"\n",(0,s.jsxs)(n.p,{children:["In the early versions of BladePipe, when synchronizing data to ClickHouse's ",(0,s.jsx)(n.strong,{children:"ReplacingMergeTree"})," table, the following strategy was followed:"]}),"\n",(0,s.jsxs)(n.ul,{children:["\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsxs)(n.p,{children:["Insert and Update statements were converted into ",(0,s.jsx)(n.strong,{children:"Insert"})," statements."]}),"\n"]}),"\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsxs)(n.p,{children:["Delete statements were separately processed using ",(0,s.jsx)(n.strong,{children:"ALTER TABLE DELETE"})," statements."]}),"\n"]}),"\n"]}),"\n",(0,s.jsxs)(n.p,{children:["Though it was effective, the performance might be affected when there were a large number of ",(0,s.jsx)(n.strong,{children:"Delete"})," statements, leading to high latency."]}),"\n",(0,s.jsxs)(n.p,{children:["In the latest version, BladePipe optimizes the synchronization logic, supporting ",(0,s.jsx)(n.code,{children:"_sign"})," and ",(0,s.jsx)(n.code,{children:"_version"})," fields in the ",(0,s.jsx)(n.strong,{children:"ReplacingMergeTree"})," table engine. All ",(0,s.jsx)(n.strong,{children:"Insert"}),", ",(0,s.jsx)(n.strong,{children:"Update"}),", and ",(0,s.jsx)(n.strong,{children:"Delete"})," statements are converted into ",(0,s.jsx)(n.strong,{children:"Insert"})," statements with version information."]}),"\n",(0,s.jsx)(n.h3,{id:"schema-migration",children:"Schema Migration"}),"\n",(0,s.jsxs)(n.p,{children:["When migrating schemas from Oracle to ClickHouse, BladePipe uses ReplacingMergeTree as the table engine by default and automatically adds ",(0,s.jsx)(n.code,{children:"_sign"})," and ",(0,s.jsx)(n.code,{children:"_version"})," fields to the table:"]}),"\n",(0,s.jsx)(n.pre,{children:(0,s.jsx)(n.code,{className:"language-sql",children:"CREATE TABLE console.worker_stats (\n `id` Int64,\n `gmt_create` DateTime,\n `worker_id` Int64,\n `cpu_stat` String,\n `mem_stat` String,\n `disk_stat` String,\n `_sign` UInt8 DEFAULT 0,\n `_version` UInt64 DEFAULT 0,\n INDEX `_version_minmax_idx` (`_version`) TYPE minmax GRANULARITY 1\n) ENGINE = ReplacingMergeTree(`_version`, `_sign`) ORDER BY `id`\n"})}),"\n",(0,s.jsx)(n.h3,{id:"data-writing",children:"Data Writing"}),"\n",(0,s.jsx)(n.h4,{id:"dml-conversion",children:"DML Conversion"}),"\n",(0,s.jsx)(n.p,{children:"During data writing, BladePipe adopts the following DML conversion strategy:"}),"\n",(0,s.jsxs)(n.ul,{children:["\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsx)(n.p,{children:"Insert statements in Source:"}),"\n",(0,s.jsx)(n.pre,{children:(0,s.jsx)(n.code,{className:"language-sql",children:"-- Insert new data, _sign value is set to 0\nINSERT INTO <schema>.<table> (columns, _sign, _version) VALUES (..., 0, <new_version>);\n"})}),"\n"]}),"\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsx)(n.p,{children:"Update statements in Source (converted into two Insert statements):"}),"\n",(0,s.jsx)(n.pre,{children:(0,s.jsx)(n.code,{className:"language-sql",children:"-- Logically delete old data, _sign value is set to 1\nINSERT INTO <schema>.<table> (columns, _sign, _version) VALUES (..., 1, <new_version>);\n\n-- Insert new data, _sign value is set to 0\nINSERT INTO <schema>.<table> (columns, _sign, _version) VALUES (..., 0, <new_version>);\n"})}),"\n"]}),"\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsx)(n.p,{children:"Delete statements in Source:"}),"\n",(0,s.jsx)(n.pre,{children:(0,s.jsx)(n.code,{className:"language-sql",children:"-- Logically delete old data, _sign value is set to 1\nINSERT INTO <schema>.<table> (columns, _sign, _version) VALUES (..., 1, <new_version>);\n"})}),"\n"]}),"\n"]}),"\n",(0,s.jsx)(n.h4,{id:"data-version",children:"Data Version"}),"\n",(0,s.jsx)(n.p,{children:"When writing data, BladePipe maintains version information for each table:"}),"\n",(0,s.jsxs)(n.ul,{children:["\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsx)(n.p,{children:"Version Initialization: During the first write, BladePipe retrieves the current table's latest version number by running:"}),"\n",(0,s.jsx)(n.pre,{children:(0,s.jsx)(n.code,{className:"language-sql",children:"SELECT MAX(`_version`) FROM `console`.`worker_stats`;\n"})}),"\n"]}),"\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsx)(n.p,{children:"Version Increment: Each time new data is written, BladePipe increments the version number based on the previously retrieved maximum version number, ensuring each write operation has a unique and incrementing version number."}),"\n"]}),"\n"]}),"\n",(0,s.jsxs)(n.p,{children:["To ensure data accuracy in queries, add the ",(0,s.jsx)(n.strong,{children:"final"})," keyword to filter out the rows that are not deleted :"]}),"\n",(0,s.jsx)(n.pre,{children:(0,s.jsx)(n.code,{className:"language-sql",children:"SELECT `id`, `gmt_create`, `worker_id`, `cpu_stat`, `mem_stat`, `disk_stat`\nFROM `console`.`worker_stats` final;\n"})}),"\n",(0,s.jsx)(n.h2,{id:"procedure",children:"Procedure"}),"\n",(0,s.jsx)(n.h3,{id:"step-1-install-bladepipe",children:"Step 1: Install BladePipe"}),"\n",(0,s.jsx)(n.p,{children:"You can use BladePipe in three ways:"}),"\n",(0,s.jsxs)(n.ol,{children:["\n",(0,s.jsxs)(n.li,{children:[(0,s.jsx)(n.strong,{children:"SaaS (Fully Managed)"})," \u2013 90-day free trial. Just log in and start using it. See ",(0,s.jsx)(n.a,{href:"https://www.bladepipe.com/docs/quick/quick_start_mgr/",children:"Qu
1ick Start (SaaS)"}),"."]}),"\n",(0,s.jsxs)(n.li,{children:[(0,s.jsx)(n.strong,{children:"BYOC (Bring Your Own Cloud)"})," \u2013 90-day free trial. Follow the instructions in ",(0,s.jsx)(n.a,{href:"https://www.bladepipe.com/docs/productOP/byoc/installation/install_worker_docker/",children:"Install Worker (Docker)"})," or ",(0,s.jsx)(n.a,{href:"https://www.bladepipe.com/docs/productOP/byoc/installation/install_worker_binary/",children:"Install Worker (Binary)"})," to download and install a BladePipe Worker."]}),"\n",(0,s.jsxs)(n.li,{children:[(0,s.jsx)(n.strong,{children:"On-premise (Local Deployment)"})," \u2013 Free community edition. Click ",(0,s.jsx)(n.strong,{children:"Try Community Free"})," on the homepage for one-click deployment. See ",(0,s.jsx)(n.a,{href:"https://www.bladepipe.com/docs/quick/quick_start/",children:"Quick Start (On-premise)"}),"."]}),"\n"]}),"\n",(0,s.jsx)(n.h3,{id:"step-2-add-datasources",children:"Step 2: Add DataSources"}),"\n",(0,s.jsxs)(n.ol,{children:["\n",(0,s.jsxs)(n.li,{children:["Log in to BladePipe:","\n",(0,s.jsxs)(n.ul,{children:["\n",(0,s.jsxs)(n.li,{children:[(0,s.jsx)(n.strong,{children:"SaaS / BYOC"}),": Log in to the ",(0,s.jsx)(n.a,{href:"https://cloud.bladepipe.com",children:"BladePipe Cloud"}),"."]}),"\n",(0,s.jsxs)(n.li,{children:[(0,s.jsx)(n.strong,{children:"On-premise"}),": Open ",(0,s.jsx)(n.code,{children:"http://${ip}:8111"})," in your browser."]}),"\n"]}),"\n"]}),"\n",(0,s.jsxs)(n.li,{children:["Click ",(0,s.jsx)(n.strong,{children:"DataSource"})," > ",(0,s.jsx)(n.strong,{children:"Add DataSource"}),"."]}),"\n",(0,s.jsxs)(n.li,{children:["Select the source and target DataSource type, and fill out the setup form respectively.\n",(0,s.jsx)(n.img,{alt:"BladePipe: add Oracle and ClickHouse DataSources",src:i(18504).A+"",width:"7220",height:"3868"})]}),"\n"]}),"\n",(0,s.jsx)(n.h3,{id:"step-3-create-a-datajob",children:"Step 3: Create a DataJob"}),"\n",(0,s.jsxs)(n.ol,{children:["\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsxs)(n.p,{children:["Click ",(0,s.jsx)(n.strong,{children:"DataJob"})," > ",(0,s.jsx)(n.a,{href:"https://www.bladepipe.com/docs/operation/job_manage/create_job/create_full_incre_task/",children:(0,s.jsx)(n.strong,{children:"Create DataJob"})}),"."]}),"\n"]}),"\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsxs)(n.p,{children:["Select the source and target DataSources, and click ",(0,s.jsx)(n.strong,{children:"Test Connection"})," to ensure the connection to the source and target DataSources are both successful."]}),"\n"]}),"\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsxs)(n.p,{children:["In the ",(0,s.jsx)(n.strong,{children:"Advanced"})," configuration of the target DataSource, choose the table engine as ",(0,s.jsx)(n.strong,{children:"ReplacingMergeTree"})," (or ",(0,s.jsx)(n.strong,{children:"ReplicatedReplacingMergeTree"}),")."]}),"\n",(0,s.jsx)(n.p,{children:(0,s.jsx)(n.img,{alt:"BladePipe: choose ClickHouse table engine ReplacingMergeTree",src:i(96835).A+"",width:"7256",height:"3880"})}),"\n"]}),"\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsxs)(n.p,{children:["Select ",(0,s.jsx)(n.strong,{children:"Incremental"})," for DataJob Type, together with the ",(0,s.jsx)(n.strong,{children:"Full Data"})," option."]}),"\n",(0,s.jsxs)(n.admonition,{type:"info",children:[(0,s.jsxs)(n.p,{children:["In the ",(0,s.jsx)(n.strong,{children:"Specification"})," settings, make sure that you select a specification of at least ",(0,s.jsx)(n.strong,{children:"1 GB"}),"."]}),(0,s.jsx)(n.p,{children:"Allocating too little memory may result in Out of Memory (OOM) errors during DataJob execution."})]}),"\n",(0,s.jsx)(n.p,{children:(0,s.jsx)(n.img,{alt:"BladePipe: set DataJob spec (memory) for Oracle to ClickHouse sync",src:i(90650).A+"",width:"7252",height:"3872"})}),"\n"]}),"\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsx)(n.p,{children:"Select the tables to be replicated."}),"\n",(0,s.jsx)(n.p,{children:(0,s.jsx)(n.img,{alt:"BladePipe: select Oracle tables to replicate to ClickHouse",src:i(59061).A+"",width:"7212",height:"3872"})}),"\n"]}),"\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsx)(n.p,{children:"Select the columns to be replicated."}),"\n",(0,s.jsx)(n.p,{children:(0,s.jsx)(n.img,{alt:"BladePipe: select columns to replicate to ClickHouse",src:i(47436).A+"",width:"7232",height:"3880"})}),"\n"]}),"\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsx)(n.p,{children:"Confirm the DataJob creation."}),"\n"]}),"\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsx)(n.p,{children:"Now the DataJob is created and started. BladePipe will automatically run the following DataTasks:"}),"\n",(0,s.jsxs)(n.ul,{children:["\n",(0,s.jsxs)(n.li,{children:[(0,s.jsx)(n.strong,{children:"Schema Migration"}),": The schemas of the source tables will be migrated to ClickHouse."]}
1),"\n",(0,s.jsxs)(n.li,{children:[(0,s.jsx)(n.strong,{children:"Full Data Migration"}),": All existing data from the source tables will be fully migrated to ClickHouse."]}),"\n",(0,s.jsxs)(n.li,{children:[(0,s.jsx)(n.strong,{children:"Incremental Synchronization"}),": Ongoing data changes will be continuously synchronized to the target database."]}),"\n"]}),"\n",(0,s.jsx)(n.p,{children:(0,s.jsx)(n.img,{alt:"BladePipe: Oracle to ClickHouse DataTasks (schema, full load, incremental sync)",src:i(22334).A+"",width:"7244",height:"1076"})}),"\n"]}),"\n"]}),"\n",(0,s.jsx)(n.h3,{id:"step-4-verify-the-data",children:"Step 4: Verify the Data"}),"\n",(0,s.jsxs)(n.ol,{children:["\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsx)(n.p,{children:"Stop data write in the Source database and wait for ClickHouse to merge data."}),"\n",(0,s.jsxs)(n.admonition,{type:"info",children:[(0,s.jsxs)(n.p,{children:["It's hard to know when ClickHouse merges data automatically, so you can manually trigger a merging by running the ",(0,s.jsx)(n.code,{children:"optimize table xxx final"})," command. Note that there is a chance that this manual merging may not always succeed."]}),(0,s.jsxs)(n.p,{children:["Alternatively, you can run the ",(0,s.jsx)(n.code,{children:"create view xxx_v as select * from xxx final"})," command to create a view and perform queries on the view to ensure the data is fully merged."]})]}),"\n"]}),"\n",(0,s.jsxs)(n.li,{children:["\n",(0,s.jsxs)(n.p,{children:[(0,s.jsx)(n.a,{href:"https://www.bladepipe.com/docs/operation/job_manage/create_job/create_period_verification_correction_job/",children:"Create a Verification DataJob"}),". Once the Verification DataJob is completed, review the results to confirm that the data in ClickHouse is the same as that in Oracle."]}),"\n",(0,s.jsx)(n.p,{children:(0,s.jsx)(n.img,{alt:"BladePipe: verification DataJob result",src:i(78089).A+"",width:"7240",height:"1036"})}),"\n"]}),"\n"]}),"\n",(0,s.jsx)(n.h2,{id:"faqs",children:"FAQs"}),"\n",(0,s.jsx)(n.h3,{id:"oracle-to-clickhouse-migration-what-are-the-top-5-features-to-compare",children:"Oracle to ClickHouse migration: what are the top 5 features to compare?"}),"\n",(0,s.jsx)(n.p,{children:"Compare these 5 must-have features for ETL or CDC tools:"}),"\n",(0,s.jsxs)(n.ul,{children:["\n",(0,s.jsx)(n.li,{children:"CDC sync: One-time or continuous real-time?"}),"\n",(0,s.jsx)(n.li,{children:"UPDATE/DELETE: Safe mutation handling in ClickHouse?"}),"\n",(0,s.jsx)(n.li,{children:"Schema evolution: Auto-handle DDL changes without breaking?"}),"\n",(0,s.jsx)(n.li,{children:"Reliability: Retries, offset resume, backpressure?"}),"\n",(0,s.jsx)(n.li,{children:"Verification: Built-in reconciliation to fix drift?"}),"\n"]}),"\n",(0,s.jsx)(n.h3,{id:"which-data-integration-tool-is-best-for-oracle-to-clickhouse",children:"Which data integration tool is best for Oracle to ClickHouse?"}),"\n",(0,s.jsx)(n.p,{children:"It depends on your ops capacity. Pick a managed platform if you need fast setup + CDC + schema handling + verification (recommended for most teams). Pick DIY if you already run streaming infra (Kafka/Flink) and want full control."}),"\n",(0,s.jsx)(n.h3,{id:"best-etl-tool-oracle-to-clickhouse-batch-or-real-time",children:"Best ETL tool Oracle to ClickHouse: batch or real-time?"}),"\n",(0,s.jsx)(n.p,{children:"The deciding factor is latency need."}),"\n",(0,s.jsxs)(n.ul,{children:["\n",(0,s.jsx)(n.li,{children:"Batch load = simpler, scheduled (hourly/daily)."}),"\n",(0,s.jsx)(n.li,{children:"Real-time CDC = near real-time sync, requires UPDATE/DELETE handling."}),"\n"]}),"\n",(0,s.jsx)(n.h3,{id:"do-i-need-cdc-for-a-one-time-oracle-to-clickhouse-migration",children:"Do I need CDC for a one-time Oracle to ClickHouse migration?"}),"\n",(0,s.jsx)(n.p,{children:"Not necessarily. For a one-time migration you can do a full load plus validation. If you also need to keep Oracle and ClickHouse in sync during a cutover (or long backfill), CDC becomes important."}),"\n",(0,s.jsx)(n.h3,{id:"how-to-avoid-data-drift-in-oracle-to-clickhouse-pipelines",children:"How to avoid data drift in Oracle to ClickHouse pipelines?"}),"\n",(0,s.jsx)(n.p,{children:"Use this 3-step checklist:"}),"\n",(0,s.jsxs)(n.ul,{children:["\n",(0,s.jsx)(n.li,{children:"Preserve transaction order."}),"\n",(0,s.jsx)(n.li,{children:"Resume from offset after failures."}),"\n",(0,s.jsx)(n.li,{children:"Run periodic verification + alert on mismatches."}),"\n"]}),"\n",(0,s.jsx)(n.h3,{id:"can-oracle-to-clickhouse-tools-support-real-time-data-pipelines",children:"Can Oracle to ClickHouse tools support real-time data pipelines?"}),"\n",(0,s.jsx)(n.p,{children:"Yes. Tools like Bladepipe support: Full load (initial snapshot); Continuous incremental sync (CDC); Ops layer: monitoring, retries, verification"})]})}function h(e={}){const{wrapper:n}={...(0,a.R)(),...e.components};return n?(0,s.jsx)(n,{...e,children:(0,s.jsx)(d,{...e})}):d(e)}},18504(e,n,i){i.d(n,{A:()=>t});const t=i.p+"assets/images/oracle_ch_1-1e34660701158dc165b09f1598a9517d.png"},96835(e,n,i){i.d(n,{A:()=>t});const t=i.p+"assets/images/oracle_ch_2-276bf25e5198264e7fcdcf5c67769aaf.png"},90650(e,n,i){i.d(n,{A:()=>t});const t=i.p+"assets/images/oracle_ch_3-bcb6dab56415ba31f2b282f3094d259b.png"},59061(e,n,i){i.d(n,{A:()=>t});const t=i.p+"assets/images/oracle_ch_4-05f5d0d3353b198e8bc96e4c74b1270f.png"},47436(e,n,i){i.d(n,{A:()=>t});const t=i.p+"assets/images/oracle_ch_5-452374664200d223e4386481dd1a1870.png"},22334(e,n,i){i.d(n,{A:()=>t});const t=i.p+"assets/images/oracle_ch_7-e84f82aa81bbd1ba2be6341aa40718c9.png"},78089(e,n,i){i.d(n,{A:()=>t});const t=i.p+"assets/images/oracle_ch_8-639638bcdf760c72530fcfe5fa62c32c.png"},28453(e,n,i){i.d(n,{R:()=>o,x:()=>r});var t=i(96540);const s={},a=t.createContext(s);function o(e){const n=t.useContext(a);return t.useMemo(function(){return"function"==typeof e?e(n):{...n,...e}},[n,e])}function r(e){let n;return n=e.disableParentContext?"function"==typeof e.components?e.components(s):e.components||s:o(e.components),t.createElement(a.Provider,{value:n},e.children)}},58200(e){e.exports=JSON.parse('{"permalink":"/blog/tech_share/oracle_clickhouse_sync","source":"@site/blog/tech_share/oracle_clickhouse_sync.md","title":"Best ETL Tool for Oracle to ClickHouse (Migration + Comparison)","description":"Looking for the best ETL/data integration tool for Oracle to ClickHouse? This guide compares options and shows how to migrate and keep data in sync (schema, deletes, and verification).","date":"2025-03-05T00:00:00.000Z","tags":[{"inline":false,"label":"Tutorials","permalink":"/blog/tags/tech_share","description":"Tutorials"}],"readingTime":7.56,"hasTruncateMarker":false,"authors":[{"name":"Barry","imageURL":"/img/authors/juantu.png","key":"juantu","page":null}],"frontMatter":{"id":"oracle_clickhouse_sync","description":"Looking for the best ETL/data integration tool for Oracle to ClickHouse? This guide compares options and shows how to migrate and keep data in sync (schema, deletes, and verification).","title":"Best ETL Tool for Oracle to ClickHouse (Migration + Comparison)","date":"2025-03-05T00:00:00.000Z","authors":"juantu","tags":["tutorials"],"image":"/img/blog/tutorials/oracle_clickhouse_sync.png"},"unlisted":false,"prevItem":{"title":"Data Verification for Migration and Replication: Methods and Checklist","permalink":"/blog/data_insights/data_verification"},"nextItem":{"title":"Sync Data from Redis to Redis - A No-code Intuitive Way","permalink":"/blog/tech_share/redis_redis_sync"}}')}}]);
Line numbers count LF bytes from the start of the resource, as the search results do. Vendor segments are library code the classifier recognised; they are stored but not indexed. Bytes are shown as Latin1 characters, one per byte.