mssql

MSSQL Writer

Generates Microsoft SQL Server DDL (Data Definition Language) from database schema models.

Features

• DDL Generation: Generates complete SQL scripts for creating MSSQL schema
• Schema Support: Creates multiple schemas with proper naming
• Bracket Notation: Uses [schema].[table] bracket notation for identifiers
• Identity Columns: Generates IDENTITY(1,1) for auto-increment columns
• Constraints: Generates primary keys, foreign keys, unique, and check constraints
• Indexes: Creates indexes with unique support
• Extended Properties: Uses sp_addextendedproperty for comments
• Direct Execution: Can directly execute DDL on MSSQL database
• Schema Flattening: Optional schema flattening for compatibility

Features by Phase

1. Phase 1: Create schemas
2. Phase 2: Create tables with columns, identity, and defaults
3. Phase 3: Add primary key constraints
4. Phase 4: Create indexes
5. Phase 5: Add unique constraints
6. Phase 6: Add check constraints
7. Phase 7: Add foreign key constraints
8. Phase 8: Add extended properties (comments)

Type Mappings

Usage

Generate SQL File

import "git.warky.dev/wdevs/relspecgo/pkg/writers/mssql"
import "git.warky.dev/wdevs/relspecgo/pkg/writers"

writer := mssql.NewWriter(&writers.WriterOptions{
    OutputPath: "schema.sql",
    FlattenSchema: false,
})

err := writer.WriteDatabase(db)
if err != nil {
    panic(err)
}

Direct Database Execution

writer := mssql.NewWriter(&writers.WriterOptions{
    OutputPath: "",
    Metadata: map[string]interface{}{
        "connection_string": "sqlserver://sa:password@localhost/newdb",
    },
})

err := writer.WriteDatabase(db)
if err != nil {
    panic(err)
}

CLI Usage

Generate SQL file:

relspec convert --from json --from-path schema.json \
                --to mssql --to-path schema.sql

Execute directly to database:

relspec convert --from json --from-path schema.json \
                --to mssql \
                --metadata '{"connection_string":"sqlserver://sa:password@localhost/mydb"}'

Default Values

The writer supports several default value patterns:

• Functions: GETDATE(), CURRENT_TIMESTAMP()
• Literals: strings wrapped in quotes, numbers, booleans (0/1 for BIT)
• CAST expressions

Comments/Extended Properties

Table and column descriptions are stored as MS_Description extended properties:

EXEC sp_addextendedproperty
  @name = 'MS_Description',
  @value = 'Table description here',
  @level0type = 'SCHEMA', @level0name = 'dbo',
  @level1type = 'TABLE', @level1name = 'my_table';

Testing

Run tests with:

go test ./pkg/writers/mssql/...

Limitations

• Views are not currently supported in the writer
• Sequences are not supported (MSSQL uses IDENTITY instead)
• Partitioning and advanced features are not supported
• Generated DDL assumes no triggers or computed columns