Fixing PLS-00302: component 'HASH_SH256' must be declared in Oracle 11g

 This error occurs when DBMS_CRYPTO.HASH_SH256 is not recognized in Oracle 11g.

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✅ Step 1: Verify DBMS_CRYPTO Package Exists

Run the following query to check if DBMS_CRYPTO is installed:

SELECT * FROM all_objects WHERE object_name = 'DBMS_CRYPTO';

🔹 If no rows are returned, the package might be missing or invalid.

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✅ Step 2: Grant Execution Privilege

Log in as SYSDBA and grant the required privilege:

GRANT EXECUTE ON DBMS_CRYPTO TO your_username;

🔹 Replace your_username with the actual Oracle user.

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✅ Step 3: Check Supported Hashing Algorithms in Oracle 11g

Oracle 11g does not support HASH_SH256. Instead, use HASH_SH1 (SHA-1) or HASH_MD5 (MD5).
Run this to verify available hashing functions:

SELECT object_name FROM all_procedures WHERE object_name LIKE 'HASH_%' AND owner = 'SYS';

🔹 Oracle 11g supports only HASH_MD5, HASH_SH1, and HASH_SH256 (in 11.2+).

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✅ Step 4: Use a Supported Hash Function

If HASH_SH256 is missing, use HASH_SH1 (SHA-1) instead:

DECLARE
    v_hashed RAW(2000);
BEGIN
    v_hashed := DBMS_CRYPTO.HASH(UTL_RAW.CAST_TO_RAW('HelloWorld'), DBMS_CRYPTO.HASH_SH1);
    DBMS_OUTPUT.PUT_LINE(RAWTOHEX(v_hashed));
END;
/

🔹 This will return a SHA-1 hash.

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✅ Step 5: Upgrade to Oracle 12c+ (If Needed)

If you must use SHA-256, you need Oracle 12c or later. Oracle 11g does not support HASH_SH256 by default.

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🔹 Summary: Fixing the Error

Issue	Solution
PLS-00302: component 'HASH_SH256' must be declared	Use HASH_SH1 or HASH_MD5 instead.
ORA-00904: invalid identifier 'DBMS_CRYPTO.HASH_SH256'	Check if DBMS_CRYPTO exists with SELECT * FROM all_objects WHERE object_name = 'DBMS_CRYPTO';
ORA-06550: Identifier 'DBMS_CRYPTO' must be declared	Run GRANT EXECUTE ON DBMS_CRYPTO TO your_username;

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Need SHA-256 in Oracle 11g?

Since Oracle 11g doesn’t support HASH_SH256, you can implement SHA-256 manually using Java Stored Procedures or external libraries.