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| MR. CHARLIE HOPKINS M 1933-07-09 Mr. | MR. CHARLIE HOPKINS M 1933-07-09 Mr. | ||
| MS. KIMBERLY BLUE F 1944-08-01 Ms. | MS. KIMBERLY BLUE F 1944-08-01 Ms. | ||
| - | KATHLEEN TUCKER F 2004-09-14 Miss</code> | + | KATHLEEN TUCKER F 2004-09-14 Miss |
| </code> | </code> | ||
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| - | {{page>:top_add&nofooter&noeditbtn}} | ||
| - | <html><div align="center"><span style="color:red">DRAFT</span></div></html> | ||
| - | ====== Omnidex SQL Function: CASE ====== | ||
| - | {{page>:sql_bar&nofooter&noeditbtn}} | ||
| - | ===== Description ===== | ||
| - | The CASE function handles simple IF - THEN - ELSE logic at a select-item level. The WHEN conditions are evaluated in order until a condition proves TRUE, at which point the THEN expression is executed. All of the THEN expressions in a CASE statement must be of the same data type: numeric, character, or date. | ||
| - | |||
| - | CASE supports multiple conditions per case. | ||
| - | |||
| - | ===== Syntax ===== | ||
| - | CASE | ||
| - | WHEN condition_expression THEN scalar_expression | ||
| - | ELSE scalar_expression | ||
| - | END | ||
| - | |||
| - | or | ||
| - | |||
| - | CASE scalar_expression_1 | ||
| - | WHEN scalar_expression_2 THEN scalar_expression_3 | ||
| - | ELSE scalar_expression_4 | ||
| - | END | ||
| - | |||
| - | ===== Example ===== | ||
| - | ==== Example 1 Condition Expression ==== | ||
| - | <code> | ||
| - | SELECT ... | ||
| - | CASE | ||
| - | WHEN PRODUCTS.CATEGORY =30 THEN 'Furniture' | ||
| - | WHEN PRODUCTS.CATEGORY = 70 THEN 'Machines' | ||
| - | WHEN PRODUCTS.CATEGORY = 90 THEN 'Paper Products' | ||
| - | ELSE 'Office Supplies' | ||
| - | END; | ||
| - | </code> | ||
| - | |||
| - | ==== Example 2 Scalar Expression ==== | ||
| - | <code SQL> | ||
| - | CASE DATES.MO | ||
| - | WHEN 'Jan' THEN 1 | ||
| - | WHEN 'Feb' THEN 2 | ||
| - | WHEN 'Mar' THEN 3 | ||
| - | WHEN 'Apr' THEN 4 | ||
| - | ELSE 0 | ||
| - | END | ||
| - | </code> | ||
| - | ==== Example 3 Select Statement with Conditional Expression ==== | ||
| - | |||
| - | <code SQL> | ||
| - | select company, | ||
| - | |||
| - | case | ||
| - | when customers.state='CA' then 'CALIFORNIA' | ||
| - | when customers.state='CO' then 'COLORADO' | ||
| - | when customers.state='NY' then 'NEW YORK' | ||
| - | when customers.state='NJ' then 'NEW JERSEY' | ||
| - | else 'OTHER' | ||
| - | end | ||
| - | |||
| - | from customers | ||
| - | where state in ('ca','co','ny','nj','az','fl','nv') | ||
| - | order by state; | ||
| - | </code> | ||
| - | |||
| - | ==== Example 4 Select Statement with Scalar Expression ==== | ||
| - | <code SQL> | ||
| - | select company, contact, | ||
| - | |||
| - | case customers.state | ||
| - | when 'AZ' then 'ARIZONA' | ||
| - | when 'FL' then 'FLORIDA' | ||
| - | when 'NV' then 'NEVADA' | ||
| - | else 'OTHER' | ||
| - | end | ||
| - | |||
| - | from customers | ||
| - | where company='systems' | ||
| - | order by state | ||
| - | </code> | ||
| - | |||
| - | {{page>:bottom_add&nofooter&noeditbtn}} | ||