SQL Expressions
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SQL expressions are special expressions in the expression language, which are converted into SQL and evaluated in an external system that supports SQL (e.g., Snowflake, SQL Server, Databricks, Redshift). Only a subset of expression language functionalities are supported by SQL expressions (which are explained in this page).
- Arithmetics operators: Addition (+), Subtraction (-), Multiplication (*), Division (/), Remainder (%)
- Comparison operators: ==, <, <=, >, >=, !=.
- Logical operators: && (AND), || (OR), ! (NOT) are used to combine expressions that return boolean values.
- Data types: strings ("this is a string"), integers (123), decimal numbers (123.45), booleans (true, false)
| Function | Parameters | Description |
|---|---|---|
| CaseWhen | Number |
Goes through conditions and returns a value when the first condition is met, similar to an if-then-else. Once a condition is true, it will stop reading and return the result. If no conditions are true, it returns the value in the else-expression. Consists of any number of pairs of condition and value expressions followed by an optional else expression. CaseWhen(Column("a") == null, 1, Column("a") < 1.0, 2, 3)
Returns 1 if the value of column "a" is null.
Returns 2 if the value of column "a" is less than 1.0.
Returns 3 otherwise.
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