# AI2SQL > AI2SQL converts plain English into SQL queries. Supports PostgreSQL, MySQL, SQL Server, SQLite, Oracle, Snowflake, BigQuery, and Redshift. ## What AI2SQL Does - Converts natural language questions into SQL queries - Supports 8+ database dialects with syntax-specific output - Validates generated queries before execution - Explains existing SQL in plain English - Optimizes slow queries with AI suggestions - Connects to live databases for schema-aware generation - Works with databases on localhost or a private network via the AI2SQL Connector, a local app that reads the schema on the user's own machine (see https://builder.ai2sql.io/connector) ## Links - [Full content guide for AI](https://builder.ai2sql.io/llms-full.txt) - [Try AI2SQL Free](https://builder.ai2sql.io/signup) - [Pricing](https://builder.ai2sql.io/dashboard/choose-plan) - [Blog](https://builder.ai2sql.io/blog) ## Blog Posts - [Should You Still Learn SQL in 2026 When AI Writes It?](https://builder.ai2sql.io/blog/should-you-learn-sql-in-2026): Anchored to r/learnSQL "Learning SQL in the age of Claude, Codex and Gemini" — why you should still learn SQL but learn it differently: reading/verifying over writing, JOIN cardinality, NULL semantics, plus a 30-day learn-with-AI plan. - [Excel Formulas to SQL: A Translation Guide for Analysts (2026)](https://builder.ai2sql.io/blog/excel-formulas-to-sql-guide): Anchored to r/analytics "Why is so much data work still in Excel?" — a side-by-side Excel-to-SQL reference (VLOOKUP→JOIN, SUMIF→GROUP BY, pivots→aggregation), the VLOOKUP fan-out trap, and AI shortcuts. - [Convert SQL Between Database Dialects with AI: A 2026 Guide](https://builder.ai2sql.io/blog/convert-sql-dialects-ai-guide): Anchored to r/dataengineering "Db migration tooling" and r/PostgreSQL "I migrated our workload from Aurora to LakeBase" — a PostgreSQL/MySQL/SQL Server/Snowflake/BigQuery dialect-difference table with worked conversions and AI-assisted migration. - [AI-Assisted Database Schema Design: A Practical Guide (2026)](https://builder.ai2sql.io/blog/ai-database-schema-design-guide): Anchored to r/dataengineering "Need Advice on Designing a Ticket Conversation Database Schema" — a real schema designed end to end with normalization, keys, and indexes, and the line between where AI helps and where it shouldn't decide. - [Using Functions in SQL Server Views: Patterns & Pitfalls (2026)](https://builder.ai2sql.io/blog/sql-server-functions-in-views-guide): Anchored to r/SQLServer "OMG! I Just Discovered Functions in Views" — scalar vs inline table-valued functions, the RBAR performance trap, SQL Server 2019 UDF inlining, and how to keep function-backed views fast. - [Update NULL Values in SQL: 5 Patterns + AI Shortcut (2026)](https://builder.ai2sql.io/blog/sql-update-null-values-guide): Anchored to r/SQL "Best way to update NULL values?" thread — 5 production patterns (plain UPDATE, COALESCE, CASE, JOIN-based, batched) with real benchmarks, gotchas, and the AI shortcut for plain-English NULL updates. - [Which SQL Tasks Should AI Handle in 2026? Reddit-Sourced Breakdown](https://builder.ai2sql.io/blog/which-sql-tasks-ai-handle-2026): 6 SQL tasks where AI saves real time vs 5 tasks humans should still own. Benchmark table covering Gemini 3.5 Flash, Claude 4.7, GPT-5.4, AI2SQL. Anchored to r/dataanalysis and r/SQL threads. - [Self-Joins in SQL Made Simple: 3 Patterns + AI Examples (2026)](https://builder.ai2sql.io/blog/sql-self-joins-guide-2026): Anchored to r/SQL "Struggling with Self-Joins" — 3 patterns (hierarchy, sequential, pair-finding) with employee/manager examples, 4 gotchas, when to use window functions or recursive CTEs instead. - [MySQL JSON Functions Guide](https://builder.ai2sql.io/blog/mysql-json-functions): JSON_EXTRACT, JSON_OBJECT, JSON_ARRAY, JSON_SET, JSON_CONTAINS with examples for MySQL 5.7+ - [MySQL to PostgreSQL Migration Guide](https://builder.ai2sql.io/blog/mysql-to-postgresql-migration): Step-by-step migration guide covering schema conversion, data type mapping, syntax differences, and tools like pgLoader - [50 SQL Interview Questions & Answers for 2026](https://builder.ai2sql.io/blog/sql-interview-questions) - [SQL Cheat Sheet: Every Command You Need](https://builder.ai2sql.io/blog/sql-cheat-sheet) - [30 SQL Query Examples for Beginners to Advanced](https://builder.ai2sql.io/blog/sql-query-examples) - [BigQuery SQL Tutorial: Complete Guide with Examples (2026)](https://builder.ai2sql.io/blog/bigquery-sql-tutorial) - [Snowflake SQL Tutorial: Complete Guide with Examples (2026)](https://builder.ai2sql.io/blog/snowflake-sql-tutorial) - [SQL CASE WHEN: Complete Guide with Examples (2026)](https://builder.ai2sql.io/blog/sql-case-when) - [SQL Joins Explained: Visual Guide with Examples](https://builder.ai2sql.io/blog/sql-joins-explained) - [How to Understand a Complex SQL Query with AI](https://builder.ai2sql.io/blog/understand-complex-sql-queries-with-ai): paste a query nobody documented, get it explained in execution order - [How to Fix a SQL Query with AI](https://builder.ai2sql.io/blog/fix-sql-queries-with-ai): paste the query and the error message, get the one change that fixes it - [How to Optimize a Slow SQL Query with AI](https://builder.ai2sql.io/blog/optimize-slow-sql-queries-with-ai): paste a slow query, get a rewrite and the reason it is faster - [How to Understand and Debug Legacy Oracle SQL](https://builder.ai2sql.io/blog/understand-and-debug-legacy-oracle-sql): ROWNUM before ORDER BY, NVL masking a failed join, and the other ERP report bugs - [How to Debug Stored Procedures with AI](https://builder.ai2sql.io/blog/debug-stored-procedures-with-ai): isolating the failing statement, parameter sniffing, transaction traps - [Best AI Tools for Oracle SQL in 2026](https://builder.ai2sql.io/blog/best-ai-tools-for-oracle-sql-2026): which tools stay in Oracle dialect instead of emitting LIMIT - [Best AI Tools for SQL Server in 2026](https://builder.ai2sql.io/blog/best-ai-tools-for-sql-server-2026): T-SQL correctness: TOP, MERGE, OFFSET FETCH, SSMS and Copilot compared - [Best AI SQL Query Optimizers in 2026](https://builder.ai2sql.io/blog/best-ai-sql-query-optimizers-2026): what a text-level optimizer fixes and where a tuning advisor is still needed - [How to Connect AI to a Local SQL Server Database](https://builder.ai2sql.io/blog/connect-ai-to-local-sql-server-database): why localhost cannot be reached by a cloud tool, and the local connector - [ChatGPT for SQL vs AI2SQL](https://builder.ai2sql.io/blog/chatgpt-for-sql-vs-ai2sql): where a general assistant is enough and where schema and dialect break it - [7 Best AI SQL Generator Tools in 2026](https://builder.ai2sql.io/blog/best-ai-sql-tools-2026) - [Text to SQL: Complete Guide to AI Query Generation](https://builder.ai2sql.io/blog/text-to-sql-complete-guide) - [What is SQL? A Complete Beginner's Guide for 2026](https://builder.ai2sql.io/blog/what-is-sql) - [SQL GROUP BY Explained: Complete Guide with Examples](https://builder.ai2sql.io/blog/sql-group-by) - [SQL WHERE Clause: Complete Guide to Filtering Data](https://builder.ai2sql.io/blog/sql-where-clause) - [SQL vs NoSQL: Which Database Should You Use in 2026?](https://builder.ai2sql.io/blog/sql-vs-nosql) - [Excel to SQL: The Complete Migration Guide for 2026](https://builder.ai2sql.io/blog/excel-to-sql) - [PostgreSQL Cheat Sheet: Every Command You Need (2026)](https://builder.ai2sql.io/blog/postgresql-cheat-sheet) - [MySQL Cheat Sheet: Every Command You Need (2026)](https://builder.ai2sql.io/blog/mysql-cheat-sheet) - [SQL Server Cheat Sheet: Every T-SQL Command (2026)](https://builder.ai2sql.io/blog/sql-server-cheat-sheet) - [SQLite Cheat Sheet: Every Command You Need (2026)](https://builder.ai2sql.io/blog/sqlite-cheat-sheet) - [Oracle SQL Cheat Sheet: Every Command You Need (2026)](https://builder.ai2sql.io/blog/oracle-sql-cheat-sheet) - [DB2 Cheat Sheet: Every SQL Command You Need (2026)](https://builder.ai2sql.io/blog/db2-cheat-sheet) - [MySQL vs PostgreSQL: Which Database Should You Use in 2026?](https://builder.ai2sql.io/blog/mysql-vs-postgresql) - [PostgreSQL vs MongoDB: Which Database Should You Use in 2026?](https://builder.ai2sql.io/blog/postgresql-vs-mongodb) - [MySQL vs SQL Server: Which Database Should You Use in 2026?](https://builder.ai2sql.io/blog/mysql-vs-sql-server) - [MySQL vs MongoDB: Which Database Should You Use in 2026?](https://builder.ai2sql.io/blog/mysql-vs-mongodb) - [SQLite vs MySQL: Which Database Should You Use in 2026?](https://builder.ai2sql.io/blog/sqlite-vs-mysql) - [MySQL vs MariaDB: Which Database Should You Use in 2026?](https://builder.ai2sql.io/blog/mysql-vs-mariadb) - [How to Use AI to Write SQL Queries: A Practical Guide (2026)](https://builder.ai2sql.io/blog/how-to-use-ai-to-write-sql-queries) - [How to Connect AI to Your SQL Server Database (Step-by-Step)](https://builder.ai2sql.io/blog/connect-ai-to-sql-server) - [What Is an AI SQL Generator? How Text-to-SQL Actually Works](https://builder.ai2sql.io/blog/what-is-ai-sql-generator) - [How to Learn SQL with AI: A Beginner's Guide (2026)](https://builder.ai2sql.io/blog/learn-sql-with-ai) - [Microsoft Access to SQL Migration: The Complete Guide (2026)](https://builder.ai2sql.io/blog/access-to-sql-migration-guide) - [How to Convert Microsoft Access Queries to SQL with AI](https://builder.ai2sql.io/blog/convert-access-queries-to-sql) - [7 Best Microsoft Access Alternatives in 2026 (With AI Features)](https://builder.ai2sql.io/blog/microsoft-access-alternatives) - [SQL CROSS APPLY Explained: Complete Guide with Examples (2026)](https://builder.ai2sql.io/blog/sql-cross-apply-guide) - [SQLBolt Alternative: Learn SQL Interactively with AI (2026)](https://builder.ai2sql.io/blog/sqlbolt-alternative) - [SQL Indexing Best Practices: The Complete Guide (2026)](https://builder.ai2sql.io/blog/sql-indexing-best-practices) - [SQL for Data Engineers: The Complete Guide (2026)](https://builder.ai2sql.io/blog/sql-for-data-engineers) - [SQL PARTITION BY: Complete Guide with Examples (2026)](https://builder.ai2sql.io/blog/sql-partition-by) - [SQL ROW_NUMBER: Complete Guide with Examples (2026)](https://builder.ai2sql.io/blog/sql-row-number) - [SQL Window Functions: The Complete Guide with Examples (2026)](https://builder.ai2sql.io/blog/sql-window-functions-complete-guide) - [MySQL vs PostgreSQL in 2026: Performance, Features, and When to Use Each](https://builder.ai2sql.io/blog/mysql-vs-postgresql-2026) - [SQL Subqueries Explained: Complete Guide with Examples (2026)](https://builder.ai2sql.io/blog/sql-subquery-guide) - [SQL for Non-Technical People: A Complete Beginner's Guide (2026)](https://builder.ai2sql.io/blog/sql-for-non-technical-people) - [SQL Triggers: Tutorial with Practical Examples (2026)](https://builder.ai2sql.io/blog/sql-triggers-tutorial) - [SQL LIKE Operator and Pattern Matching: Complete Guide (2026)](https://builder.ai2sql.io/blog/sql-like-operator-pattern-matching) - [DuckDB vs SQLite vs PostgreSQL: Which Database Should You Choose? (2026)](https://builder.ai2sql.io/blog/duckdb-vs-sqlite-vs-postgresql) - [SQL CRUD Operations: INSERT, SELECT, UPDATE, DELETE Explained (2026)](https://builder.ai2sql.io/blog/sql-crud-operations-guide) - [SQL for Data Science: Essential Queries Every Data Scientist Needs (2026)](https://builder.ai2sql.io/blog/sql-for-data-science) - [Best AI Database Assistant Tools Compared (2026)](https://builder.ai2sql.io/blog/ai-database-assistant-tools-2026) - [SQL vs Python for Data Analysis: Which Should You Learn First? (2026)](https://builder.ai2sql.io/blog/sql-vs-python-data-analysis) - [SQL Stored Procedures: Complete Guide with Examples (2026)](https://builder.ai2sql.io/blog/sql-stored-procedures-guide) - [ChatGPT for SQL Queries: Can It Replace a Query Builder? (2026)](https://builder.ai2sql.io/blog/chatgpt-for-sql-queries) - [AI2SQL MCP Server for Claude Code: Query Databases from Your Terminal (2026)](https://builder.ai2sql.io/blog/ai2sql-mcp-claude-code) - [Microsoft SQL MCP Server vs AI2SQL MCP: Which One Should You Use](https://builder.ai2sql.io/blog/microsoft-sql-mcp-vs-ai2sql) - [How to Query Your Database with Natural Language in 2026](https://builder.ai2sql.io/blog/query-database-natural-language-2026) - [Why AI-Generated SQL Makes Developers Nervous (And How to Fix It)](https://builder.ai2sql.io/blog/ai-generated-sql-safety-guide) - [The Most Common SQL Mistakes and How AI Catches Them](https://builder.ai2sql.io/blog/common-sql-mistakes-ai-detection) - [SQL Interview Questions AI Can Solve in Seconds](https://builder.ai2sql.io/blog/sql-interview-questions-ai-practice) - [Oracle MERGE INTO: Complete Tutorial with Examples](https://builder.ai2sql.io/blog/oracle-merge-into-tutorial) - [What is SQL? The Ultimate Guide for Beginners](https://builder.ai2sql.io/blog/what-is-sql-guide-beginners): Learn what SQL is, how it works, and why it matters. Includes real examples and how AI tools simplify database queries. - [DAX vs SQL: Complete Guide for Data Analysts in 2026](https://builder.ai2sql.io/blog/dax-vs-sql): DAX and SQL are both query languages for data analysis — but they work very differently. Learn when to use DAX vs SQL, key syntax differences, and how AI2SQL can help with SQL queries. ## SQL Converter Tools - [All Converters](https://builder.ai2sql.io/convert) - [MySQL to PostgreSQL Converter](https://builder.ai2sql.io/convert/mysql-to-postgresql) - [PostgreSQL to MySQL Converter](https://builder.ai2sql.io/convert/postgresql-to-mysql) - [MySQL to SQL Server Converter](https://builder.ai2sql.io/convert/mysql-to-sql-server) - [SQL Server to MySQL Converter](https://builder.ai2sql.io/convert/sql-server-to-mysql) - [Oracle to PostgreSQL Converter](https://builder.ai2sql.io/convert/oracle-to-postgresql) - [Oracle to SQL Server Converter](https://builder.ai2sql.io/convert/oracle-to-sql-server) - [SQLite to MySQL Converter](https://builder.ai2sql.io/convert/sqlite-to-mysql) - [SQLite to PostgreSQL Converter](https://builder.ai2sql.io/convert/sqlite-to-postgresql) - [CSV to SQL Converter](https://builder.ai2sql.io/convert/csv-to-sql) - [JSON to SQL Converter](https://builder.ai2sql.io/convert/json-to-sql) - [MySQL to DB2 Converter](https://builder.ai2sql.io/convert/mysql-to-db2) - [PostgreSQL to DB2 Converter](https://builder.ai2sql.io/convert/postgresql-to-db2) - [SQL Server to DB2 Converter](https://builder.ai2sql.io/convert/sql-server-to-db2) - [Oracle to DB2 Converter](https://builder.ai2sql.io/convert/oracle-to-db2) ## SQL Error Reference - [MySQL Error 1045: Access Denied for User](https://builder.ai2sql.io/blog/mysql-error-1045-access-denied) - [MySQL Error 1064: SQL Syntax Error](https://builder.ai2sql.io/blog/mysql-error-1064-syntax-error) - [MySQL Error 1146: Table Doesn't Exist](https://builder.ai2sql.io/blog/mysql-error-1146-table-doesnt-exist) - [MySQL Error 1062: Duplicate Entry for Key](https://builder.ai2sql.io/blog/mysql-error-1062-duplicate-entry) - [MySQL Error 2002: Can't Connect to Local Server](https://builder.ai2sql.io/blog/mysql-error-2002-cant-connect) - [PostgreSQL Error 42P01: Relation Does Not Exist](https://builder.ai2sql.io/blog/postgresql-error-42p01-relation-does-not-exist) - [PostgreSQL Error 23505: Unique Violation](https://builder.ai2sql.io/blog/postgresql-error-23505-unique-violation) - [PostgreSQL Error 42601: Syntax Error](https://builder.ai2sql.io/blog/postgresql-error-42601-syntax-error) - [PostgreSQL Error 28P01: Authentication Failed](https://builder.ai2sql.io/blog/postgresql-error-28p01-authentication-failed) - [SQL Server Error 208: Invalid Object Name](https://builder.ai2sql.io/blog/sql-server-error-208-invalid-object-name) - [SQL Server Error 547: Foreign Key Constraint Conflict](https://builder.ai2sql.io/blog/sql-server-error-547-foreign-key-conflict) - [SQL Server Error 102: Incorrect Syntax](https://builder.ai2sql.io/blog/sql-server-error-102-incorrect-syntax) - [SQL Server Error 18456: Login Failed](https://builder.ai2sql.io/blog/sql-server-error-18456-login-failed) - [Oracle Error ORA-00942: Table or View Does Not Exist](https://builder.ai2sql.io/blog/oracle-error-ora-00942-table-does-not-exist) - [Oracle Error ORA-01017: Invalid Username/Password](https://builder.ai2sql.io/blog/oracle-error-ora-01017-invalid-credentials) - [Oracle Error ORA-12154: TNS Could Not Resolve](https://builder.ai2sql.io/blog/oracle-error-ora-12154-tns-could-not-resolve) - [SQLite Error: Database Is Locked](https://builder.ai2sql.io/blog/sqlite-error-database-is-locked) - [SQLite Error: No Such Table](https://builder.ai2sql.io/blog/sqlite-error-no-such-table) - [Oracle Error ORA-00904: Invalid Identifier](https://builder.ai2sql.io/blog/oracle-error-ora-00904-invalid-identifier) - [Oracle Error ORA-01722: Invalid Number](https://builder.ai2sql.io/blog/oracle-error-ora-01722-invalid-number) - [MySQL Error 1054: Unknown Column in 'field list'](https://builder.ai2sql.io/blog/mysql-error-1054-unknown-column) - [PostgreSQL Error 42703: Column Does Not Exist](https://builder.ai2sql.io/blog/postgresql-error-42703-column-does-not-exist) - [SQL Server Error 2627: Violation of PRIMARY KEY Constraint](https://builder.ai2sql.io/blog/sql-server-error-2627-duplicate-key) ## SQL How-to Guides - [How to Create an Index in MySQL](https://builder.ai2sql.io/blog/how-to-create-index-mysql) - [How to Create an Index in PostgreSQL](https://builder.ai2sql.io/blog/how-to-create-index-postgresql) - [How to Pivot a Table in SQL](https://builder.ai2sql.io/blog/how-to-pivot-table-sql) - [How to Insert Multiple Rows in MySQL](https://builder.ai2sql.io/blog/how-to-insert-multiple-rows-mysql) - [How to Insert Multiple Rows in PostgreSQL](https://builder.ai2sql.io/blog/how-to-insert-multiple-rows-postgresql) - [How to UPDATE with JOIN in MySQL](https://builder.ai2sql.io/blog/how-to-update-join-mysql) - [How to UPDATE with JOIN in SQL Server](https://builder.ai2sql.io/blog/how-to-update-join-sql-server) - [How to Delete Duplicate Rows in SQL](https://builder.ai2sql.io/blog/how-to-delete-duplicate-rows-sql) - [How to Find the Nth Highest Salary in SQL](https://builder.ai2sql.io/blog/how-to-find-nth-highest-salary-sql) - [How to Convert String to Date in SQL](https://builder.ai2sql.io/blog/how-to-convert-string-to-date-sql) - [How to Add a Column in MySQL](https://builder.ai2sql.io/blog/how-to-add-column-mysql) - [How to Add a Column in PostgreSQL](https://builder.ai2sql.io/blog/how-to-add-column-postgresql) - [How to Backup a MySQL Database](https://builder.ai2sql.io/blog/how-to-backup-mysql-database) - [How to Use Window Functions in SQL](https://builder.ai2sql.io/blog/how-to-use-window-functions-sql) - [How to Use CTEs in SQL](https://builder.ai2sql.io/blog/how-to-use-cte-sql) ## SQL Function Reference - [SQL CONCAT Function](https://builder.ai2sql.io/blog/sql-concat-function): Guide to SQL CONCAT function with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL SUBSTRING Function](https://builder.ai2sql.io/blog/sql-substring-function): Guide to SQL SUBSTRING function with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL REPLACE Function](https://builder.ai2sql.io/blog/sql-replace-function): Guide to SQL REPLACE function with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL TRIM Function](https://builder.ai2sql.io/blog/sql-trim-function): Guide to SQL TRIM function with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL UPPER and LOWER Functions](https://builder.ai2sql.io/blog/sql-upper-lower-function): Guide to SQL UPPER and LOWER functions with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL LENGTH/LEN Function](https://builder.ai2sql.io/blog/sql-length-function): Guide to SQL LENGTH/LEN function with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL LEFT and RIGHT Functions](https://builder.ai2sql.io/blog/sql-left-right-function): Guide to SQL LEFT and RIGHT functions with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL REVERSE Function](https://builder.ai2sql.io/blog/sql-reverse-function): Guide to SQL REVERSE function with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL CHARINDEX/POSITION/INSTR Function](https://builder.ai2sql.io/blog/sql-charindex-position-function): Guide to SQL CHARINDEX, POSITION, and INSTR functions with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL NOW/CURRENT_TIMESTAMP Function](https://builder.ai2sql.io/blog/sql-now-current-timestamp-function): Guide to SQL NOW and CURRENT_TIMESTAMP functions with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL DATEADD/DATE_ADD Function](https://builder.ai2sql.io/blog/sql-dateadd-date-add-function): Guide to SQL DATEADD and DATE_ADD functions with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL DATEDIFF Function](https://builder.ai2sql.io/blog/sql-datediff-function): Guide to SQL DATEDIFF function with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL DATE_FORMAT/TO_CHAR Function](https://builder.ai2sql.io/blog/sql-date-format-function): Guide to SQL DATE_FORMAT and TO_CHAR functions with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL EXTRACT/DATEPART Function](https://builder.ai2sql.io/blog/sql-extract-datepart-function): Guide to SQL EXTRACT and DATEPART functions with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL DATE_TRUNC Function](https://builder.ai2sql.io/blog/sql-date-trunc-function): Guide to SQL DATE_TRUNC function with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL COUNT Function](https://builder.ai2sql.io/blog/sql-count-function): Guide to SQL COUNT function with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL SUM, AVG, MIN, MAX Functions](https://builder.ai2sql.io/blog/sql-sum-avg-min-max-function): Guide to SQL SUM, AVG, MIN, and MAX aggregate functions with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL GROUP_CONCAT/STRING_AGG Function](https://builder.ai2sql.io/blog/sql-group-concat-string-agg-function): Guide to SQL GROUP_CONCAT and STRING_AGG functions with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL COALESCE Function](https://builder.ai2sql.io/blog/sql-coalesce-function): Guide to SQL COALESCE function with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL NULLIF Function](https://builder.ai2sql.io/blog/sql-nullif-function): Guide to SQL NULLIF function with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL CAST/CONVERT Function](https://builder.ai2sql.io/blog/sql-cast-convert-function): Guide to SQL CAST and CONVERT functions with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL ROUND, CEIL, FLOOR Functions](https://builder.ai2sql.io/blog/sql-round-ceil-floor-function): Guide to SQL ROUND, CEIL, and FLOOR functions with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL ABS, MOD, POWER Functions](https://builder.ai2sql.io/blog/sql-abs-mod-power-function): Guide to SQL ABS, MOD, and POWER functions with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL RAND/RANDOM Function](https://builder.ai2sql.io/blog/sql-random-function): Guide to SQL RAND and RANDOM functions with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL CASE WHEN Statement](https://builder.ai2sql.io/blog/sql-case-when-function): Guide to SQL CASE WHEN statement with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [SQL JSON Functions](https://builder.ai2sql.io/blog/sql-json-functions): Guide to SQL JSON functions with syntax and examples for MySQL, PostgreSQL, SQL Server, and Oracle - [Natural Language Database Queries](https://builder.ai2sql.io/blog/natural-language-database-query): How to ask your database questions in plain English, real translation examples, accuracy tips, and best practices for phrasing queries - [SQL Recursive Queries and CTEs: Tutorial with Examples](https://builder.ai2sql.io/blog/sql-recursive-queries-guide): Learn recursive CTEs with practical examples for org charts, category trees, bill of materials, path finding, and date series generation - [How Text-to-SQL LLMs Work](https://builder.ai2sql.io/blog/text-to-sql-llm-guide): How LLMs convert natural language to SQL, schema-aware prompting, accuracy benchmarks, and common failure modes - [Snowflake vs BigQuery vs Redshift](https://builder.ai2sql.io/blog/snowflake-vs-bigquery-vs-redshift): Cloud data warehouse comparison on pricing, storage, compute, SQL dialect, ML features, and when to choose each - [Oracle vs PostgreSQL](https://builder.ai2sql.io/blog/oracle-vs-postgresql): Enterprise database comparison with migration guide, syntax conversion examples, and common migration pitfalls - [Oracle PL/SQL to Serverless PostgreSQL Migration](https://builder.ai2sql.io/blog/oracle-plsql-to-postgresql-serverless-migration): Hands-on PL/SQL to PL/pgSQL conversion map, package and procedure rewrites, serverless gotchas (connection pooling, cold starts, schedulers), and when to move logic to Lambda vs keep it in the database - [SQL for Data Analytics](https://builder.ai2sql.io/blog/sql-for-data-analytics): 12 analytics query patterns for KPI dashboards, cohort analysis, funnel analysis, retention, revenue metrics, and A/B testing - [SQL Injection Prevention Guide](https://builder.ai2sql.io/blog/sql-injection-prevention-guide): What SQL injection is, how attacks work, prevention techniques with code examples in Python, Node.js, Java, PHP - [AI SQL Debugging: Self-Healing Queries](https://builder.ai2sql.io/blog/ai-sql-debugging-self-healing): How AI detects and fixes SQL errors automatically with self-healing query feedback loops - [MCP for Databases](https://builder.ai2sql.io/blog/mcp-database-model-context-protocol): Model Context Protocol explained for databases, MCP servers, setup examples, and benefits for schema-aware AI - [SQL for Product Managers](https://builder.ai2sql.io/blog/sql-for-product-managers): 10 essential SQL queries every PM needs for DAU/MAU, retention, conversion funnels, churn analysis, and A/B testing - [AI2SQL MCP Server for Claude Code](https://builder.ai2sql.io/blog/ai2sql-mcp-claude-code): How to use the AI2SQL MCP server with Claude Code to query databases directly from your terminal using natural language ## Free Tools - [SQL Playground](https://builder.ai2sql.io/sql-playground): Free interactive in-browser SQL playground (sql.js + CodeMirror) with 8 guided exercises covering SELECT, JOIN, GROUP BY, HAVING, and subqueries. A modern SQLBolt alternative — no signup required. - [SQL Interview Questions for FAANG (2026): Real Questions From Meta, Google, Amazon, Apple, Netflix](https://builder.ai2sql.io/blog/sql-interview-questions-faang): SQL interview questions asked at FAANG (Meta, Google, Amazon, Apple, Netflix) in 2026 — with runnable answers, common traps, and the patterns interviewers really test. - [SQL Window Functions Interview Questions (2026): 6 Real Questions With Runnable Answers](https://builder.ai2sql.io/blog/sql-window-functions-interview): SQL window functions interview questions with answers — ROW_NUMBER, RANK, DENSE_RANK, LAG/LEAD, running totals, percent of total. Covers the patterns asked at FAANG and high-bar data roles in 2026. - [SQL JOIN Interview Questions (2026): 8 Real Questions With Answers](https://builder.ai2sql.io/blog/sql-join-interview-questions): SQL JOIN interview questions with runnable answers — INNER, LEFT, RIGHT, FULL OUTER, SELF, CROSS, anti-join, semi-join. Covers the most common JOIN patterns interviewers test in 2026. - [SQL Aggregate Functions Interview Questions (2026): COUNT, SUM, AVG, GROUP BY With Real Examples](https://builder.ai2sql.io/blog/sql-aggregate-functions-interview): SQL aggregate function interview questions with answers — COUNT(*) vs COUNT(column), GROUP BY traps, HAVING vs WHERE, DISTINCT pitfalls, ROLLUP and CUBE. Real questions from data interviews in 2026. - [SQL Syntax Checker: How to Find and Fix SQL Errors Online (2026)](https://builder.ai2sql.io/blog/sql-syntax-checker): How to check SQL syntax online: free tools compared, the 12 most common syntax errors with fixes, and dialect-specific traps for PostgreSQL, MySQL, and SQL Server. - [SQL Practice Exercises With Answers: 50 Beginner to Advanced Problems (2026)](https://builder.ai2sql.io/blog/sql-practice-exercises): 50 SQL practice exercises with runnable answers — from SELECT basics to window functions, recursive CTEs, and pivot patterns. Solve, run, and level up your SQL.