Initial commit: Romanian ERP database migration system

Complete project setup with:
- PACK_MIGRARE utility package
- Migration script examples and patterns
- Comprehensive documentation in CLAUDE.md and README.md
- System instructions for SQL generation

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-Authored-By: Claude <noreply@anthropic.com>

CLAUDE.md

@@ -0,0 +1,111 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Project Overview
+
+This is a Romanian ERP database migration system for Oracle databases. The project generates DDL/DML migration scripts following strict naming conventions and safety patterns to ensure idempotent execution.
+
+## Key Architecture Components
+
+### PACK_MIGRARE Package
+Central utility package (`system_instructions/knowledge_base/PACK_MIGRARE.pck`) that provides:
+- `ColumnExist()` - Check if column exists before adding
+- `ObjectExist()` - Check if database object exists  
+- `ConstraintExist()` - Check if constraint exists
+- `UpdateVersiune()` - Version tracking for migration scripts
+
+### Migration Scripts Examples
+You have multiple example migration scrips in `system_instructions/knowledge_base`
+
+### Migration Script Structure
+All migration scripts must follow this pattern:
+1. Use PACK_MIGRARE functions to check existence before creating/modifying objects
+2. Wrap DDL operations in PL/SQL blocks with existence checks
+3. Use MERGE with NOT MATCHED clause for data insertions to prevent duplicates
+4. End with `pack_migrare.UpdateVersiune('script_name')` call
+5. Add brief Romanian comment at top describing changes
+
+### Naming Conventions
+- Script files: `ff_YYYY_MM_DD_NN_TYPE.sql` (e.g., `ff_2024_08_28_02_COMUN_EFACTURA.sql`)
+- No schema names in DDL statements
+- No quotes around table/column names
+- Uppercase SQL keywords
+- Romanian comments
+
+## SQL Formatting Rules
+
+**NEVER use:**
+- Schema qualifiers (`"MARIUSM_AUTO"."JV2007"`)
+- Quotes around object names (`"COLUMN_NAME"`)
+
+**ALWAYS use:**
+- Uppercase SQL keywords (`ALTER TABLE`, `ADD`, `NUMBER`)
+- Existence checks via PACK_MIGRARE before DDL operations
+- Default values and NOT NULL constraints for new columns
+- `NUMBER(18,4) DEFAULT 0 NOT NULL` for monetary/tax columns
+
+## Common Migration Patterns
+
+### 1. Adding Columns (with existence check)
+```sql
+BEGIN
+    IF PACK_MIGRARE.COLUMNEXIST('TABLE_NAME', 'COLUMN_NAME') = 0 THEN
+        EXECUTE IMMEDIATE 'ALTER TABLE TABLE_NAME ADD COLUMN_NAME NUMBER(18,4) DEFAULT 0 NOT NULL';
+    END IF;
+END;
+/
+COMMENT ON COLUMN TABLE_NAME.COLUMN_NAME IS 'Romanian description';
+```
+
+### 2. Inserting Configuration Data (MERGE with NOT MATCHED)
+```sql
+MERGE INTO OPTIUNI a USING DUAL b ON (a.varname = 'CONFIG_KEY')
+WHEN NOT MATCHED THEN
+INSERT (VARNAME, VARTYPE, VARVALUE, VARDESC)
+VALUES ('CONFIG_KEY', 'CHARACTER', 'value', 'Descriere in romana');
+```
+
+### 3. Inserting System Objects (with complex conditions)
+```sql
+MERGE INTO DEF_OBIECTE a USING DUAL b ON (a.id_obiect = 6089)
+WHEN NOT MATCHED THEN
+INSERT (ID_OBIECT, ID_PROGRAM, DESCRIERE, ID_TATA, COD, ID_UTILOP, DATAORA, STERS)
+VALUES (6089, 2, 'Descriere obiect', 6082, '02', -3, SYSDATE, 0);
+```
+
+### 4. Creating/Replacing Views
+```sql
+CREATE OR REPLACE VIEW view_name AS
+SELECT column1, column2
+FROM table_name
+WHERE conditions;
+```
+
+### 5. Simple Updates
+```sql
+UPDATE OPTIUNI SET VARVALUE = '1' 
+WHERE VARNAME IN ('OPTION1', 'OPTION2');
+
+UPDATE ANAF_EFACTURA_DETALII SET ARTICOL = TRIM(ARTICOL);
+```
+
+### 6. Script Completion (ALWAYS required)
+```sql
+exec pack_migrare.UpdateVersiune('ff_2024_MM_DD_NN_TYPE');
+commit;
+```
+
+## Directory Structure
+
+- `input/` - Input files and table definitions  
+- `output/` - Generated migration scripts
+- `system_instructions/` - Project documentation and examples (see [README](system_instructions/README.md) for details)
+- `system_instructions/knowledge_base/` - Reference scripts and PACK_MIGRARE package
+
+## Important Notes
+
+- All scripts must be idempotent (safe to run multiple times)
+- Never include NULL values or CLOB data in INSERT/MERGE statements
+- Use direct DDL for COMMENT statements, not EXECUTE IMMEDIATE
+- Script names must be dynamic based on current date