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+# Oracle Database Conversion Guide
+
+## Table of Contents
+1. [Introduction](#introduction)
+2. [Data Type Mappings](#data-type-mappings)
+3. [Syntax Differences](#syntax-differences)
+4. [Common Issues](#common-issues)
+5. [Examples](#examples)
+
+## Introduction
+This guide provides detailed information about converting Oracle database schemas to and from other database systems using SQLMapper.
+
+## Data Type Mappings
+
+### Oracle to MySQL
+| Oracle Type | MySQL Type | Notes |
+|------------|------------|-------|
+| NUMBER(p,s) | DECIMAL(p,s) | For exact numeric values |
+| NUMBER | BIGINT | When no precision specified |
+| VARCHAR2 | VARCHAR | - |
+| CLOB | LONGTEXT | - |
+| BLOB | LONGBLOB | - |
+| DATE | DATETIME | - |
+| TIMESTAMP | TIMESTAMP | - |
+
+### Oracle to PostgreSQL
+| Oracle Type | PostgreSQL Type | Notes |
+|------------|-----------------|-------|
+| NUMBER(p,s) | NUMERIC(p,s) | - |
+| VARCHAR2 | VARCHAR | - |
+| CLOB | TEXT | - |
+| BLOB | BYTEA | - |
+| DATE | TIMESTAMP | - |
+| TIMESTAMP | TIMESTAMP | - |
+
+## Syntax Differences
+
+### Sequences
+Oracle:
+```sql
+CREATE SEQUENCE my_sequence
+    START WITH 1
+    INCREMENT BY 1
+    NOCACHE
+    NOCYCLE;
+```
+
+MySQL equivalent:
+```sql
+CREATE TABLE my_sequence (
+    id BIGINT NOT NULL AUTO_INCREMENT,
+    PRIMARY KEY (id)
+);
+```
+
+PostgreSQL equivalent:
+```sql
+CREATE SEQUENCE my_sequence
+    START 1
+    INCREMENT 1
+    NO CYCLE;
+```
+
+### Stored Procedures
+Oracle:
+```sql
+CREATE OR REPLACE PROCEDURE update_employee(
+    p_emp_id IN NUMBER,
+    p_salary IN NUMBER
+)
+IS
+BEGIN
+    UPDATE employees 
+    SET salary = p_salary 
+    WHERE employee_id = p_emp_id;
+END;
+/
+```
+
+MySQL equivalent:
+```sql
+DELIMITER //
+CREATE PROCEDURE update_employee(
+    IN p_emp_id INT,
+    IN p_salary DECIMAL(10,2)
+)
+BEGIN
+    UPDATE employees 
+    SET salary = p_salary 
+    WHERE employee_id = p_emp_id;
+END //
+DELIMITER ;
+```
+
+## Common Issues
+
+### 1. Date Format Differences
+Oracle's default date format differs from other databases. Use explicit format strings:
+```sql
+-- Oracle
+TO_DATE('2023-12-27', 'YYYY-MM-DD')
+
+-- MySQL
+STR_TO_DATE('2023-12-27', '%Y-%m-%d')
+
+-- PostgreSQL
+TO_DATE('2023-12-27', 'YYYY-MM-DD')
+```
+
+### 2. Sequence Usage
+When converting sequences, be aware that:
+- MySQL doesn't support sequences natively
+- PostgreSQL sequences require explicit nextval() calls
+- Oracle sequences can be used in DEFAULT values
+
+### 3. NULL Handling
+Oracle treats empty strings as NULL, while other databases distinguish between empty strings and NULL values.
+
+## Examples
+
+### Converting Table with Identity Column
+```sql
+-- Original Oracle Table
+CREATE TABLE employees (
+    emp_id NUMBER GENERATED ALWAYS AS IDENTITY,
+    name VARCHAR2(100),
+    salary NUMBER(10,2),
+    hire_date DATE,
+    CONSTRAINT pk_emp PRIMARY KEY (emp_id)
+);
+
+-- MySQL Conversion
+CREATE TABLE employees (
+    emp_id BIGINT AUTO_INCREMENT,
+    name VARCHAR(100),
+    salary DECIMAL(10,2),
+    hire_date DATETIME,
+    PRIMARY KEY (emp_id)
+);
+
+-- PostgreSQL Conversion
+CREATE TABLE employees (
+    emp_id SERIAL,
+    name VARCHAR(100),
+    salary NUMERIC(10,2),
+    hire_date TIMESTAMP,
+    PRIMARY KEY (emp_id)
+);
+```
+
+### Converting Complex Types
+```sql
+-- Oracle Table with Complex Types
+CREATE TABLE documents (
+    doc_id NUMBER,
+    content CLOB,
+    metadata VARCHAR2(4000),
+    binary_data BLOB,
+    CONSTRAINT pk_doc PRIMARY KEY (doc_id)
+);
+
+-- MySQL Conversion
+CREATE TABLE documents (
+    doc_id BIGINT,
+    content LONGTEXT,
+    metadata JSON,
+    binary_data LONGBLOB,
+    PRIMARY KEY (doc_id)
+);
+
+-- PostgreSQL Conversion
+CREATE TABLE documents (
+    doc_id BIGINT,
+    content TEXT,
+    metadata JSONB,
+    binary_data BYTEA,
+    PRIMARY KEY (doc_id)
+);
+``` 
diff --git a/docs/sqlserver.md b/docs/sqlserver.md
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+# SQL Server Database Conversion Guide
+
+## Table of Contents
+1. [Introduction](#introduction)
+2. [Data Type Mappings](#data-type-mappings)
+3. [Syntax Differences](#syntax-differences)
+4. [Common Issues](#common-issues)
+5. [Examples](#examples)
+
+## Introduction
+This guide provides detailed information about converting SQL Server database schemas to and from other database systems using SQLMapper.
+
+## Data Type Mappings
+
+### SQL Server to MySQL
+| SQL Server Type | MySQL Type | Notes |
+|----------------|------------|-------|
+| BIGINT | BIGINT | - |
+| INT | INT | - |
+| SMALLINT | SMALLINT | - |
+| TINYINT | TINYINT | Range differences |
+| DECIMAL(p,s) | DECIMAL(p,s) | - |
+| VARCHAR(n) | VARCHAR(n) | - |
+| NVARCHAR(n) | VARCHAR(n) | UTF-8 encoding |
+| TEXT | LONGTEXT | - |
+| DATETIME2 | DATETIME | Precision differences |
+| UNIQUEIDENTIFIER | CHAR(36) | - |
+
+### SQL Server to PostgreSQL
+| SQL Server Type | PostgreSQL Type | Notes |
+|----------------|-----------------|-------|
+| BIGINT | BIGINT | - |
+| INT | INTEGER | - |
+| SMALLINT | SMALLINT | - |
+| DECIMAL(p,s) | NUMERIC(p,s) | - |
+| VARCHAR(n) | VARCHAR(n) | - |
+| NVARCHAR(n) | VARCHAR(n) | - |
+| TEXT | TEXT | - |
+| DATETIME2 | TIMESTAMP | - |
+| UNIQUEIDENTIFIER | UUID | - |
+
+## Syntax Differences
+
+### Identity Columns
+SQL Server:
+```sql
+CREATE TABLE users (
+    id INT IDENTITY(1,1) PRIMARY KEY,
+    username VARCHAR(50)
+);
+```
+
+MySQL equivalent:
+```sql
+CREATE TABLE users (
+    id INT AUTO_INCREMENT PRIMARY KEY,
+    username VARCHAR(50)
+);
+```
+
+PostgreSQL equivalent:
+```sql
+CREATE TABLE users (
+    id SERIAL PRIMARY KEY,
+    username VARCHAR(50)
+);
+```
+
+### Stored Procedures
+SQL Server:
+```sql
+CREATE PROCEDURE UpdateEmployee
+    @EmpID INT,
+    @Salary DECIMAL(10,2)
+AS
+BEGIN
+    UPDATE Employees 
+    SET Salary = @Salary 
+    WHERE EmployeeID = @EmpID;
+END;
+```
+
+MySQL equivalent:
+```sql
+DELIMITER //
+CREATE PROCEDURE UpdateEmployee(
+    IN p_EmpID INT,
+    IN p_Salary DECIMAL(10,2)
+)
+BEGIN
+    UPDATE Employees 
+    SET Salary = p_Salary 
+    WHERE EmployeeID = p_EmpID;
+END //
+DELIMITER ;
+```
+
+## Common Issues
+
+### 1. Collation Differences
+SQL Server uses different collation naming conventions:
+```sql
+-- SQL Server
+COLLATE SQL_Latin1_General_CP1_CI_AS
+
+-- MySQL
+COLLATE utf8mb4_general_ci
+
+-- PostgreSQL
+COLLATE "en_US.utf8"
+```
+
+### 2. DateTime Handling
+```sql
+-- SQL Server
+GETDATE()
+DATEADD(day, 1, GETDATE())
+
+-- MySQL
+NOW()
+DATE_ADD(NOW(), INTERVAL 1 DAY)
+
+-- PostgreSQL
+CURRENT_TIMESTAMP
+CURRENT_TIMESTAMP + INTERVAL '1 day'
+```
+
+### 3. String Concatenation
+```sql
+-- SQL Server
+SELECT FirstName + ' ' + LastName
+
+-- MySQL
+SELECT CONCAT(FirstName, ' ', LastName)
+
+-- PostgreSQL
+SELECT FirstName || ' ' || LastName
+```
+
+## Examples
+
+### Converting Table with Computed Columns
+```sql
+-- Original SQL Server Table
+CREATE TABLE orders (
+    order_id INT IDENTITY(1,1),
+    quantity INT,
+    unit_price DECIMAL(10,2),
+    total_price AS (quantity * unit_price),
+    CONSTRAINT pk_orders PRIMARY KEY (order_id)
+);
+
+-- MySQL Conversion
+CREATE TABLE orders (
+    order_id INT AUTO_INCREMENT,
+    quantity INT,
+    unit_price DECIMAL(10,2),
+    total_price DECIMAL(10,2) GENERATED ALWAYS AS (quantity * unit_price) STORED,
+    PRIMARY KEY (order_id)
+);
+
+-- PostgreSQL Conversion
+CREATE TABLE orders (
+    order_id SERIAL,
+    quantity INT,
+    unit_price NUMERIC(10,2),
+    total_price NUMERIC(10,2) GENERATED ALWAYS AS (quantity * unit_price) STORED,
+    PRIMARY KEY (order_id)
+);
+```
+
+### Converting Table with Custom Types
+```sql
+-- SQL Server Table with Custom Types
+CREATE TABLE customer_data (
+    id INT IDENTITY(1,1),
+    customer_code UNIQUEIDENTIFIER DEFAULT NEWID(),
+    status VARCHAR(20),
+    metadata NVARCHAR(MAX),
+    CONSTRAINT pk_customer PRIMARY KEY (id)
+);
+
+-- MySQL Conversion
+CREATE TABLE customer_data (
+    id INT AUTO_INCREMENT,
+    customer_code CHAR(36) DEFAULT (UUID()),
+    status VARCHAR(20),
+    metadata JSON,
+    PRIMARY KEY (id)
+);
+
+-- PostgreSQL Conversion
+CREATE TABLE customer_data (
+    id SERIAL,
+    customer_code UUID DEFAULT gen_random_uuid(),
+    status VARCHAR(20),
+    metadata JSONB,
+    PRIMARY KEY (id)
+);
+```