google-big-queryHow can I use the CASE WHEN statement in Google Big Query?

The CASE WHEN statement in Google Big Query is a powerful tool for creating conditional statements in SQL. It allows you to evaluate a set of expressions and return a result based on the evaluation.

For example, the following code block can be used to create a new column in Big Query that returns a string value based on the value of another column:

SELECT
  CASE
    WHEN column1 < 0 THEN 'Negative'
    WHEN column1 = 0 THEN 'Zero'
    ELSE 'Positive'
  END AS new_column
FROM my_table

The output of this code will be a new column in the table called new_column which will contain the string value Negative, Zero, or Positive depending on the value of column1.

The syntax of the CASE WHEN statement is as follows:

CASE
  WHEN expression1 THEN result1
  WHEN expression2 THEN result2
  ...
  ELSE resultN
END

The expression can be any valid Big Query expression, such as a comparison expression, a function, etc. The result can be any valid Big Query expression, such as a string, an integer, a column, etc.

For more information on the CASE WHEN statement in Big Query, please refer to the official documentation.

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