# Multi-Table Joiner Merge and join multiple tables with various join types (inner, left, right, full) > Canonical page: https://elysiatools.com/en/tools/multi-table-joiner - **Category:** Data Processing - **Keywords:** join, merge, table, database, sql, left join, right join, inner join, full join, multi-table joiner ## Overview The Multi-Table Joiner is a powerful utility designed to merge and join datasets from multiple tables using standard SQL-style join operations, allowing you to consolidate information based on shared key columns. ## Inputs - **Input Tables** (textarea): Enter two tables separated by empty lines. Each table should have consistent column structure. - **Delimiter** (select) - **First Row Contains Headers** (checkbox) - **Join Type** (select) - **Left Table Key Column** (text): Enter column name from left table - **Right Table Key Column** (text): Enter column name from right table - **Custom Join Condition (Optional)** (text): Additional condition for filtering joined records (for advanced users) - **Output Separator** (select) - **Include Headers in Output** (checkbox) - **Preserve Source Table Info** (checkbox) ## When to use - When you need to combine two datasets that share a common identifier, such as a User ID or Product SKU. - When you want to perform data analysis by linking disparate spreadsheets or CSV files without writing complex SQL queries. - When you need to identify missing records or discrepancies between two related data sources using full or outer joins. ## How it works - Paste your source tables into the input area, ensuring they share a consistent structure and column format. - Select your preferred join type, such as Inner, Left, Right, or Full, to define how records should be matched. - Specify the key columns from both the left and right tables that the tool should use to perform the join. - Configure your output preferences, including the delimiter and header inclusion, then generate your merged dataset. ## Use cases - Merging customer contact information with order history tables using a shared Customer ID. - Comparing product inventory lists from two different warehouses to identify stock discrepancies. - Combining employee payroll data with department records to generate comprehensive staff reports. ## Frequently asked questions ### What join types are supported? The tool supports Inner, Left, Right, Full, and Cross joins to accommodate various data relationship requirements. ### Do my tables need to have the same column names? No, but they must have consistent data types in the key columns you select for the join operation. ### Can I use this tool for large datasets? The tool is optimized for browser-based processing; for extremely large files, ensure your browser has sufficient memory available. ### What happens if a key is missing in one of the tables? Depending on the join type selected, the tool will either exclude the record (Inner Join) or include it with null values for the missing fields (Left, Right, or Full Join). ### Can I add custom conditions to the join? Yes, you can use the Custom Join Condition field to apply advanced filtering logic beyond simple key matching. ## Related tools - [CSV Flavor to SQL INSERT Emitter](https://elysiatools.com/en/tools/csv-flavor-to-sql-insert-emitter): Parse CSV/Excel-CSV/TSV (auto dialect, RFC 4180) into MySQL/PostgreSQL/SQLite/SQL Server INSERT batches with type inference and ON CONFLICT/IGNORE - [Data Append Merger](https://elysiatools.com/en/tools/data-append-merger): Vertically append and merge multiple data tables with intelligent column matching - [SQL Dialect Bridge](https://elysiatools.com/en/tools/sql-dialect-bridge): Translate SQL between MySQL, PostgreSQL, SQLite, BigQuery, Snowflake, and Redshift — DDL, DML, functions and types, with UNSUPPORTED warnings - [Column Calculator](https://elysiatools.com/en/tools/column-calculator): Perform calculations on columns and add new rows - [Data Column Extractor](https://elysiatools.com/en/tools/data-column-extractor): Extract specific columns from tabular data with support for various formats and flexible column selection - [Feature Scaler](https://elysiatools.com/en/tools/feature-scaler): Scale and normalize features using various methods for machine learning preprocessing and data standardization - [Row Calculator](https://elysiatools.com/en/tools/row-calculator): Perform calculations on each row and add new columns - [Column Reorder](https://elysiatools.com/en/tools/column-reorder): Reorder table columns without changing the data rows ## Samples - [MySQL Database Samples](https://elysiatools.com/en/samples/mysql-database-samples): Sample MySQL database scripts with various complexity levels from simple tables to enterprise ERP systems - [Android Database Java Samples](https://elysiatools.com/en/samples/android-database-java): Android Java database examples including SQLite connection, SQL queries, and transaction processing - [Android Database Kotlin Samples](https://elysiatools.com/en/samples/android-database-kotlin): Android Kotlin database examples including SQLite connection, SQL queries, and transaction processing - [Drizzle ORM Samples](https://elysiatools.com/en/samples/drizzle): Drizzle ORM lightweight TypeScript ORM examples including schema definition, queries, migrations, relationships, and database patterns ## Related content - [Database Schema, Migration, and SQL Workflow Tools](https://elysiatools.com/en/hubs/database-schema-migration): Plan table schemas, generate SQL, compare database changes, validate relationships, and move spreadsheet data into database-ready formats in one hub. - [SQL Query Review, Performance, and Relational Integrity Tools](https://elysiatools.com/en/hubs/sql-query-review-performance-and-integrity): Review SQL before it reaches production: format queries, assemble joins, inspect EXPLAIN plans, catch injection patterns, validate foreign keys, and compare schema drift in one focused hub.