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Sr. Cassandra Dba/hadoop Admin Resume

Atlanta, GA


  • I have been working a Cassandra/NoSQL/Hadoop/BigData/Database Expert with over 17 years’ experience in Information technology; 5+ years’ experience with Designing, engineering, and administering Cassandra/Hadoop/BigData/NoSQL environment;
  • Designed, Installed and Configured Large Cassandra Clusters;
  • Migrated Data from Oracle to Hadoop (HDFS) for data analysis;
  • Performed data load on large databases from Oracle 11g/12c into Large Hadoop and Cassandra clusters in multiple data centers;
  • Automated Data analytical tasks through PLSQL, HQL, BASH Shell scripts;
  • I have written various complicated Hive queries (HQL) on Hive.
  • Tuned various NoSQL Databases in Cassandra 1.x/2.x/3.x.
  • I possess extensive experience in designing the Databases for OLTP and Data warehouse, Data Conversion, Data & Volumetric Analysis, Database Security Administration, Storage and Application infrastructure & enterprise model management experience.
  • I have proven demonstration of analytical and problem - solving skills with team participation skills; excellent verbal and written communication skills, developing and administering best practices.


Programming Languages: Java 1.7/1.8, Scala, MapReduce, Sparks, SQL Programming, PL/SQL Programming, Unix C, Korn, Bash Shell Scripting, DOS Scripting, VBS Scripting, AWK, SED

Database Technologies: 9i/10g/11g/12c Real Application Cluster (RAC), Oracle Gloden Gate 10/11, Data Guard, RMAN, Database Replay, STATSPACK, Explain Plan, Auto Trace, ADDM, AWR, Export/Import/DATAPUMP, SQL*Loader, MySQL

BigData/NoSQL: DSE 4.x/5.x, Cassandra 1.x/2.x/3.x, Opscenter, Hadoop 1.x/2.x, HDFS, Cassandra, Java, Sqoop, Hive, HBase, Map Reduce, Apache Spark, Scala, Sqoop

Operating System: Sun Solaris 9/10/11, AIX 5.x/6.x, RHEL/Oracle enterprise Linux, Windows 2k3, 2k8 HP-UX 11i


Confidential - Atlanta, GA

Sr. Cassandra DBA/Hadoop Admin


  • Architect/Designed Data Model for Cassandra/NoSQL databases for OMS/Pricing environment for many use cases with Application teams/Devops; Design and implement NoSQL database systems of Cassandra database clusters THD Pricing/Sales analytical systems;
  • Designed data modeling for Cassandra environment and keyspace/column family design, database coding, and database performance tuning and making schematic for Cassandra database architecture; Tuned Cassandra systems with various tuning techniques such as manual compaction, diagnosing freezing/unresponsive Cassandra peers;
  • Performed Capacity planning for Cassandra database setup and designed/implemented rollout plans for Cassandra clusters among data centers with NetworkTopologyStrategy and GossipPropertyFileSnitch; Administered Cassandra peers/clusters on Dev/QA/Prod environments;
  • Architect Multi-Data Center Cassandra clusters for THD environment; Architect multi-data center clusters with various snitches on THD Private cloud, AWS S3 and Google Cloud; Achieved data ingestion from Oracle into Cassandra 2.x/3.x; Created Cassandra column familes and tuned queries in CQL; Managed and Tuned batch/scheduled jobs on Cassandra databases and re-engineered the data model to avoid adhoc and batch jobs on Cassandra;
  • Architect/Tuned Cassandra clusters/nodes with garbage collection tuning, appropriate compaction strategy setup, tuning the large number of tombstones, tuned large SSTables and partitions; Studied performance model of Cassandra clusters and analyzed the queries for tunable consistency with various consistent levels;
  • Designed, Installed and Configured 30 node Hadoop Clusters 2.x; Migrated Data from Oracle and MySQL into HDFS for data analysis; Performed data load on large databases from Oracle 11g/12c into Hadoop/HDFS using Sqoop;
  • Leading the efforts of tuning Hadoop Datanodes to scale up the test results in tune with the requirement of the application team; Optimizing the downtime for maintenance by coordinating with the different application teams involved in the maintenance activity;
  • Participated in design/develop Bigdata infrastructure environment for THD Clearance Optimization and Price engine project; Installed and configured Hadoop 1.x/2.x; Configured HDFS for storing the data content for analysis; Performed data-load from Oracle RDBMS into Hadoop Big-data;
  • Participated in design and development of Hadoop Map reduce programs to implement the pricing and clearance pricing algorithm; Used Design and develop Hadoop Map reduce programs to implement the pricing and clearance pricing algorithm such as Hive, HBase; Design and develop Hadoop Map reduce programs to implement the pricing and clearance pricing algorithm;
  • Automated Data analytical tasks through PLSQL, HQL, BASH Shell scripts; Worked on various performance techniques on Hive such partitions, buckets, CBO; Tuned Hadoop systems (HDFS) for better performance; Performed the unit testing, integration testing and system testing of the applications.

ENVIRONMENT: Cassandra 1.x/2.x, HBase, Hadoop 1.x, 2.x.x, Hive 0.13/0.14/2. x, Sqoop, Map Reduce, Gloden Gate 10/11, KSH/BASH Shell, NoSQL

Confidential, San Francisco, CA

Sr. DBA Oracle/Cassandra/Hadoop/NoSQL


  • Performed Data upgrades from RDBMS into Cassandra databases; Build Hadoop Clusters under RHEL 6/7 environment; Analyzed data on Oracle database to move from Oracle 11g into HDFS filesystems;
  • Performed databases upgrades using 11g Data guard/In-place oracle upgrades; Accomplished PCI Compliance data migration on Confidential Credit Card database; Upgraded the Credit card database into 11gR2; Designed and implemented process for Tokenizing the user and profile credit card data into the credit card database; Tuned the system post data migration and tokenization; Designed data encryption and validation procedures for tokenized credit cards;
  • Partnered application and infrastructure architects and teams to engineer complex technical product in order to provide palpable business solutions to various business divisions as a part of DBA Engineering project activities; Architecting Oracle Fail safe environments for site critical databases, including configurations, failover testing, tuning, creating standards etc.
  • Accomplished OMS(Sterling product) upgrades with Phase-I and Phase-II; Tuned long running queries on the database servers for OMS(Sterling) calls; Tuned Oracle systems for Sterling to stabilize the query performance with stress tests and key-note tests;
  • Designed Disaster recovery strategies and performed production switch over on 5 Node RAC clusters with 4 Standby databases for ATG and OMS databases; Designed and implemented DR drill before the switch over between sites with flashback technology;
  • Designed archiving techniques for moving on large table data quarterly from production SEPHPR into SEPHARC; Automated the process of data archiving with shell scripts and PLSQL; Improved performance on the production database after the data archive; Designed compressed tables for archiving database to reduce SAN storage; Lead the DBA team on architecture council meetings for production issues, changes, design decisions, application database, system and storage infrastructure upgrades;
  • Analyzed performance issues with AWR, ADDM reports for dead locks/graphs/traces, Tuning parallel queries, Oracle and system waits, Latch Contentions, CPU/Memory high watermark analysis on peak hours, Tables and Indexes fragmentation and analysis, Collect optimizer stats for tables and indexes and fixes on stale Materialized views and refresh jobs; Troubleshooting of Performance and Tuning problems in Oracle database using tools like AWR, ASH, ADDM, SATSPACK, OEM Grid Control and manual scripts.

ENVIRONMENT: Cassandra 1.x, Hadoop 1.x, 2.x.x, Hive 0.13/0.14/2. x, Sqoop, Oracle 10g/11g/12c RAC, Data Guard, Solaris 8/9/10, RHEL 6.x/7.x, RMAN, RAC, DG, Sterling and ATG eCommerce products, NoSQL, Hadoop/Hive

Confidential, Santa Clara, CA

Sr. Database Architect


  • Responsibilities include Data Center Migration of all infrastructure components including hardware/network/storage/database; Designed/developed/implemented complete upgrade/migration plans for PSVS, PBRM PDWH (Transaction and reporting databases) running on Oracle to Real Application Clusters
  • Worked with Infrastructure management/Release management/Application/Business management to implement hardware/server/storage/network/database during Data Center Migration (DCM); Also involved in Network configuration and performance tuning for TCP UDP buffers for database interconnect tuning/Disk/ASM/AIO filesystem tuning and relevant OS kernel parameter changes
  • Worked closely with Application Business users, Application architects, System analysts, Business analysts, Storage analysts, Network exports and Oracle BDEs/Architects on Oracle Corp to identify and resolve many critical issues with given time line for the business satisfaction; Designed backup strategies for 11gR2 databases using RMAN/Veritas Netbackup/EMC BCV Sync and Split/Raid technologies
  • Upgraded more TEMPthan 30 production Shareplex Channels running on source and target database as part of production database 11g upgrades. Implemented monitoring capabilities for Shareplex channels. Fixed the bugs/issues encountered on Shareplex during the upgrade and post upgrade; Upgraded/Deployed large installations of OEM Grid Control after the database 11gR2 upgrades; Re-designed new configuration changes/scripts/functionalities on 11gR2 Databases/VCS upgraded resources/Upgraded Shareplex Channels/Netbackup configurations/Standby & Dataguard database configurations;
  • Designed and implemented Gloden Gate for database upgrades from Oracle to; Managed large initial loads/datapumps and lags for data loading; Provided extensive support after the upgrade, the issues related to performance with Gloden Gate 11 and Oracle grid infrastructure.
  • Performed benchmarks and stress tests with databases upgraded using Gloden Gate/Data guard/In-place oracle upgrades. Documented the benefits of the Oracle GG 11 over other upgrades; Attended day-to-day issues on GG such as lags, performance issues, bugs and worked with Gloden Gate support to fix the issues on production environment;
  • Arranged team meetings to discuss critical issues on war rooms, business continuity discussions, Infrastructure upgrade and new build plans, Oracle and AIX product support team meetings and escalations; Technical exchange training; Attended Project management program and Oracle Gloden Gate 11 extensive training

ENVIRONMENT: Oracle 10g/11g Solaris 8/9/10, Redhat Linux 4/5/6, Gloden Gate 10/11, Shareplex 7.4/7.5, RMAN, RAC, DG, Hitachi/Netapp Storage, Veritas Netbackup 5.x, VCS, EMC tools, SFRAC

Confidential, Brisbane, CA

DBA Architect


  • Responsibilities included design, development and support production 24x7 Oracle 9i, 10g & 11g databases in Confidential, Confidential .com, CANADA GM; Providing Database build/support project plans, LOEs for Confidential US GM e-commerce for database scaling, changes, migrations and upgrades;
  • Implemented ORACLE REAL APPLICATION CLUSTER technology to Confidential and MTEP tenants for scaling database hardware resources and increasing the availability (HA Solutions) of the database systems; Participated on all the critical issues encountered during various phases of discharging RAC for various applications such as Order/Inventory/Catalog applications;
  • Designed and documented blueprints for HA (RAC) solutions, Disaster recovery (between East and North data centers), Replication technologies for Confidential, US GM and CANADA GM; Created process standards for database maintenance such as entire site down, application down
  • Designed the process for Holiday Performance/Capacity Planning for all Confidential e-commerce tenants; Arranged multiple levels of Stress/Load tests on Database and application with keynotes and other application testing vendors on the production site; Identified the key bottlenecks during the site stress tests and generated postmortem results with detailed analysis based on order processed/min and other businesses requirements
  • Designed Site monitoring strategy on Nagios/Proactive Net for Order Management System, Catalog Inventory, Payment Gateway, Credit card authorization, Customer Relationship Management databases for Siteops/Database Admins to support the database 24x7 with pagers and alerts; Written SQL/PLSQL scripts and BASH/KSH/SH shell programs for monitoring RAC, ASM and Oracle databases;
  • Provided valuable suggestions/solutions on everyday war rooms for every production critical issues faced during the holiday and attended lessons learnt training everyday to understand issues faced on Database, Storage, Network, Operating System, Web services, Application, Monitoring
  • Analyzed and resolved issues such as DDL/DML locks and instance level locks and latch contention, enqueues and waitevents, ITL issues, Invalid objects, hourly and daily AWR reports (Automatic Workload Repository), Tablespace High Water Mark, Max datafiles limit, Top SQLs with 10046/10053 trace analysis, Top Active Sessions, blocking sessions, highly utilized datafile volumes, dump file growth, ORA errors, database parameter changes, database memory hit ratios, Partition growth, Indexes utilization/tuning, Soft/Hard parsing, Undo and Temp segment’s growth and shrinks, ORA 600/7445/4031/60/3113 errors, Standby read only status check, Log Shipping and Log Apply disaster recovery/ archived log shipping;

Confidential, San Jose, CA

Principle DBA


  • Design, development and support production 24x7 Oracle 9i, 10g & 11g databases in various configurations such as RAC, Dataguard, GG on Sun Solaris and AIX 5L and also L2/L3 Production support by troubleshooting database issues, performance monitoring/tuning & capacity planning on RAC, Dataguard, ASM, performance and scalability issues; Provided timely solutions everyday critical issues encountered across production databases to L2 Support NOC at Confidential and Worked with Oracle Support/TAR resolutions; Guide the NOC to follow up the maintenance procedures on Off-Peak hours such as Failovers, Patching, Upgrades, Data Load, ETL;
  • Implemented Oracle Gloden Gate for replicating the large tables on remote site for reporting; Attended all kind of problems encountered during the daily database operations with GG and tuned GG to replicate faster to the target systems; Prepare GlodenGate parameter files for Extraction and Replication; Investigate Replication failures using LogDump utility; Attended advanced training on Gloden Gate 11 and Cross-Train other DBAs on on Confidential database environment and Gloden Gate replication setup.
  • Portrayed and implemented the migration from 9i Manual Standby to 10g, 11g Active physical DataGuard; Resolved the critical issues involved during the migration phase such as minimizing the recovery time of DG, Tuned the network parameters for DG, Maintained Logs on DR, 8 hours Lag standby, ETL standbys (4 per each production boxes on various locations)
  • Provided Solutions for Optimal Network Configuration on Confidential databases having high volume of connections such as Network buffer configuration, OLTP Listener maintenance, Tuning the Oracle connection pool for OLTP on shared server, Interconnect Failover techniques for RAC, Tuning Interconnection for Cache coherency waits due to interconnect bottleneck, Set up Optimal SDU, TDU and buffer sizing for Data Guard for log shipping
  • Maintained large tables and indexes using Online redefinition and Online re-organization; Converted large Non-Partition tables to Range and list Partitioned table using online Re-Organization;
  • Tuned Large Confidential production database’s Complex Queries and ETL operations having very large tables and indexes; Analyzed, Identified the bottleneck of the database’s performance and adopted the optimal solutions for the slowness;
  • Designed automated scripts for monitoring the databases, alerting, alarming for spikes, top SQLs; Monitored production and standby databases using SQL scripts and Unix scripts, Identified the bottleneck of the performance during the peak hours
  • Provided timely solutions for Production On-Call issues such as Block corruptions, Performance issues, Locks and Latches on Memory, Tuning Long running SQLs, Point in Time restore and Recover

Confidential, Columbus, Ohio



  • Accomplished CROSS PLATFORM MIGRATION of Oracle 8/8i/9i on Solaris 2.x production databases to Oracle RAC on AIX (for Home Mortgage/Retail Services such as Webstats, SMART portal and NPLOS); Worked with System Administration, Network, Storage teams to design High availability and High performance systems; Designed Oracle File System layout according to the load on the Chase databases;
  • Implemented Disaster recovery and Reporting solutions using Oracle Data Guard with the help of Oracle physical and logical standbys with minimal downtime while the live is active and used by the customers
  • Suggested and Coordinated Databases changes during SAN migration such as moving SAN disks to Enterprise Array, Resource addition such as Memory, CPU on the LPAR on the Database host, Failover techniques on RAC such as Interconnect upgrades; Also applied database changes such as huge DMLs, Add, Rebuild, Drop Local/Global Indexes through Chase
  • Designed backup procedure for the large 24x7 production databases to back up on Disks and Tape Robots Weekly Full/ Everyday incremental; Maintained the retention of Database backups and Archive log backups; Designed and implemented various backup/recovery solutions to CHASE and WAMU database; Designed Purging the old backups of datafiles and archived backups; Designed monitoring systems for any backup status, alerts, errors;
  • Worked with Application/UAT team for helping to move the production data over QA systems using exp/imp, data pump utilities; Tuned the new long running SQLs which have been added to production for application code changes; Tested and implemented various Oracle tuning techniques for application to retrieve the data quicker TEMPthan earlier such as Oracle Tuning Parameters, AWR, ADDM, PLAN stability, Adding Indexes, Parallelizing queries, Optimizer hints
  • Implemented on 24x7 Oracle Audit/Security procedures for various purpose on the database to capture the failed logons, password retries, DDL/DML encountered and etc;
  • Planned Gloden Gate setup to achieve Unidirectional/Bidirectional replications for Chase mortgage databases and upgrades; Perform POC for testing DDL and DML on OGG replication across Databases; Estimate SAN Storage needed for Replication across multiple sites for GG replication; Test impact of multiple Extract and Replicat processes on a Single Node;

Confidential, Mountain View, CA



  • Responsibilities also include providing various backup solutions for COMCAST SPOTLIGHT, DISH NETWORK, NBC UNIVERSAL, TIME WARNER Cable; Designed various Backup Strategies on Tape Robots; Improving performance of the EDA and Data MART reporting databases on the Advertising;
  • Migrated and implemented the process for Confidential 's Advertising Software for Cabling Companies databases upgrades/migration for Eclipse to Eclipse Plus product on Production/Non-Production Environment oracle 9i Stand-alone databases running Windows 2000 to Oracle 10g Real Application Cluster databases (Oracle RAC) on Windows 2003 5.0 with Automatic Storage Management (ASM) using RCONFIG, Exp/Imp, 10g Data Pump; Also Documented the whole process of migration on Dev/QA/Production;
  • Designed Various backup strategies for RAC environment on Disk and Tape Storage using RMAN and VERITAS NET BACKUP; Maintained FULL, Incremental, Archived log backups, Recovery Catalogs; Restored and repaired corrupted OCR and Voting disks on live production databases; Restored the live backup on RAC to Single instance from Tape shipped from site to UAT; Resolved RAC hanging issues during the reboot on the entire cluster;
  • Resolved performance issues encountered on RAC such as OCR and Voting disk corruption, TABLE/INDEX TUNING, Analyze the long running queries on RAC databases, Tuning Interconnect for RAC, Oracle RAC specific db parameter study and setup/changes on production environment, Tuning CPU, Network, I/O for RAC, Analyzed various database wait events on board after the RAC implementation such as Global Buffer busy and other Global Cache waits with Oracle support; Worked with Oracle for various ORA Errors encountered across RAC nodes and provided them RAC specific Diagnostic logs and Trace logs to find the root cause;


Senior Database Administrator


  • Supported Data Conversion Phase I implementation to production. Built a staff calendar webpage using PL/SQL and Oracle Web Server 3.0. Tested the feasibility of Oracle Parallel Server on 8i for PDM. Implemented strategies to load 757 model data using ERWin from the legacy systems into Production.
  • Involved Conceptual and Physical Database design; Normalized Table (Commodity) containing 360 columns into 12 different tables and changed the all the SQLs and DMLs running against the table commodity which was primary accessed by CBEC (Central Board of Excise and Customs); Partitioned the table commodity with local and global indexes to avoid FTS
  • Designed and Written 15000 lines of BASH/CSH/KSH Unix Shell Scripts/SQL/PLSQL to construct Manual Replication Environment using Oracle Materialized views and PLSQL stored procedures to replicate Master Site (NRM - National Risk Manager which should of all the data) and Client ( LRM Local Risk Manager - 25 locations)
  • Accomplished the initial data load into the RMS which was about to take 5-7 days of data; Adopted various techniques on site to make the data loader faster such as adding parallel threads, huge DB BUFFER BLOCKs, More I/O slaves for each disk, High network bandwidth; Populated data from Embedded system applications (ICE GATE) into RMS (Risk management system) Database after the initial data load;
  • Designed jobs to collect the daily statistics of tables and indexes to get the best explain plan by CBO; Facilitated application team to design complex queries and PL/SQL blocks;
  • Designed the entire database structure of iJET application; Involved in the Requirements gathering phase from the Business Users, Data integration and document design; Provided document for data dictionary (Contains explanations about all database schema objects such as Tables, Indexes, Clusters, Materialized views, Packages, Stored procedures and Triggers) to application team and database team to understand about the database architecture
  • Improved performance by exhaustive performance tuning which included moving complicated business logic from the application to database, identifying poorly written SQL, SQL without bind variables, and appropriate indexing. Recommended Multipool configuration for weblogic applications; Tuned complex queries using Explain Plan, SQL TRACE with TKProf and dynamic performance views to improve the performance of query processing
  • Administered binary and raw file in database using Large object using DBMS LOBS package; Applied object oriented concepts to utilize the oracle’s resource both collection and object views; Maintained database Integrity through Key Constraints and Check Constraints

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