Average Annual Salary
SQL Server DBA - £57,500
SQL Server Developer - £52,500
Comparative Salary - £55,000
Scenarios
Scenario A - Company X requires 4 hours per week (£300)
Scenario B - Company X requires 8 hours per week (£550)
Scenario C - Company X requires 12 hours per week (£800)
Scenario D - Company X requires 8 hours per month (£550)
Scenario E - Company X requires 12 hours per month (£800)
Scenario F - Company X requires 35 hours per month (£2250)
Measurable Annual Savings
Scenario A - Total Cost = £15,600, Total Savings = £39,400
Scenario B - Total Cost = £28,600, Total Savings = £26,400
Scenario C - Total Cost = £41,600, Total Savings = £13,400
Scenario D - Total Cost = £6,600, Total Savings = £48,400
Scenario E - Total Cost = £9,600, Total Savings = £45,400
Scenario F - Total Cost = £27,000, Total Savings = £28,000
Notes:
Savings are considerably larger than stated when including benefits such as pension, holidays, sickness, health insurance etc.
SQL Server DBAs are generally responsible for the configuration, installation, and maintenance of a SQL Server and its hardware.
SQL Server Developers write T-SQL code, create supporting indexes, suggest and implement architecture, and tune performance.
The average SQL Server Professional will be one or the other, therefore to compare equally to the variety of work we can perform for your company, we should really consider two permanent employees or one, more expensive, highly skilled SQL Server Professional.
Average Salary Sources:
    SQL Server DBA:     CWJobs Salary Checker SQL DBA
    SQL Server Developer:     CWJobs Salary Checker SQL Developer