[Solved] Oracle SQL Query Really slow on a view but not actual table?

How to optimize this SQL query?

In case you have your own slow SQL query, you can optimize it automatically here.

For the query above, the following recommendations will be helpful as part of the SQL tuning process.
You'll find 3 sections below:

  1. Description of the steps you can take to speed up the query.
  2. The optimal indexes for this query, which you can copy and create in your database.
  3. An automatically re-written query you can copy and execute in your database.
The optimization process and recommendations:
  1. Avoid Selecting Unnecessary Columns (query line: 2): Avoid selecting all columns with the '*' wildcard, unless you intend to use them all. Selecting redundant columns may result in unnecessary performance degradation.
The optimized query:
SELECT
        t.*,
        CASE 
            WHEN LENGTH(t.CUSTOMER_NO) != '6' 
            AND t.text LIKE '%Nike%' 
            OR t.CUSTOMER_NO IS NULL 
            AND t.text LIKE '%Nike%' THEN 'NIK001' 
            WHEN LENGTH(t.CUSTOMER_NO) != '6' 
            AND t.text LIKE '%Nike%' 
            OR t.CUSTOMER_NO IS NULL 
            AND t.text LIKE '%Reebok%' THEN 'REB001' 
            ELSE t.CUSTOMER_NO END AS CUSTOMER_NO_ADJUSTED 
FROM
gen_led_voucher_row_tab t

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* original question posted on StackOverflow here.