[Solved] Losing indexing table in Oracle

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Losing indexing table in Oracle

Database type:

I had a table with char(20) datatype column and i indexed this column.When i do:

select * from ex_table where charColumn = 'abc'

Exception No_Data_Found raised.Because data is 'abc '.How i can search like this without losing indexing?Thanks for helping!

How to optimize this SQL query?

The following recommendations will help you in your 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.
  2. Create Optimal Indexes (modified query below): The recommended indexes are an integral part of this optimization effort and should be created before testing the execution duration of the optimized query.
Optimal indexes for this query:
CREATE INDEX ex_table_idx_charcolumn ON ex_table (charColumn);
The optimized query:
SELECT
        * 
    FROM
        ex_table 
    WHERE
        ex_table.charColumn = 'abc'

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* original question posted on StackOverflow here.