Some question about FBI and Index on unique column
Anyone can explain for me this issues.
1/ Which function-based-index(FBI) should I create and not ?
I heared from stranger who active in this forum that we should avoid create FBI as RTRIM, TO_CHAR, UPPER, TRUNC, others are ok. Is it true? And why?
2/ For ex: I have an Index like "IX_STUDENTS_STUDENTID_CLASSID_NAME_DOB"
In that, STUDENTS is table, STUDENTID is PK, CLASSID is Unique.
And I have a procedure that contain the statement: SELECT CLASSID, NAME FROM STUDENTS WHERE CLASSID = '8A'.
Of course it will use the index "IX_STUDENTS_STUDENTID_CLASSID_NAME_DOB".
And my question is: should I create an index like IX_STUDENTS_CLASSID. This might be a silly question to ask but sometimes, I saw the SQL Tuning Advisor recommended about create it.
oracle-12c index-tuning
asked 13 mins ago
WindyWindy
1
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Anyone can explain for me this issues.
1/ Which function-based-index(FBI) should I create and not ?
I heared from stranger who active in this forum that we should avoid create FBI as RTRIM, TO_CHAR, UPPER, TRUNC, others are ok. Is it true? And why?
2/ For ex: I have an Index like "IX_STUDENTS_STUDENTID_CLASSID_NAME_DOB"
In that, STUDENTS is table, STUDENTID is PK, CLASSID is Unique.
And I have a procedure that contain the statement: SELECT CLASSID, NAME FROM STUDENTS WHERE CLASSID = '8A'.
Of course it will use the index "IX_STUDENTS_STUDENTID_CLASSID_NAME_DOB".
And my question is: should I create an index like IX_STUDENTS_CLASSID. This might be a silly question to ask but sometimes, I saw the SQL Tuning Advisor recommended about create it.
oracle-12c index-tuning
asked 13 mins ago
WindyWindy
1
New contributor
Windy is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
Anyone can explain for me this issues.
1/ Which function-based-index(FBI) should I create and not ?
I heared from stranger who active in this forum that we should avoid create FBI as RTRIM, TO_CHAR, UPPER, TRUNC, others are ok. Is it true? And why?
2/ For ex: I have an Index like "IX_STUDENTS_STUDENTID_CLASSID_NAME_DOB"
In that, STUDENTS is table, STUDENTID is PK, CLASSID is Unique.
And I have a procedure that contain the statement: SELECT CLASSID, NAME FROM STUDENTS WHERE CLASSID = '8A'.
Of course it will use the index "IX_STUDENTS_STUDENTID_CLASSID_NAME_DOB".
And my question is: should I create an index like IX_STUDENTS_CLASSID. This might be a silly question to ask but sometimes, I saw the SQL Tuning Advisor recommended about create it.
oracle-12c index-tuning
asked 13 mins ago
WindyWindy
1
New contributor
Windy is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Anyone can explain for me this issues.
1/ Which function-based-index(FBI) should I create and not ?
I heared from stranger who active in this forum that we should avoid create FBI as RTRIM, TO_CHAR, UPPER, TRUNC, others are ok. Is it true? And why?
2/ For ex: I have an Index like "IX_STUDENTS_STUDENTID_CLASSID_NAME_DOB"
In that, STUDENTS is table, STUDENTID is PK, CLASSID is Unique.
And I have a procedure that contain the statement: SELECT CLASSID, NAME FROM STUDENTS WHERE CLASSID = '8A'.
Of course it will use the index "IX_STUDENTS_STUDENTID_CLASSID_NAME_DOB".
And my question is: should I create an index like IX_STUDENTS_CLASSID. This might be a silly question to ask but sometimes, I saw the SQL Tuning Advisor recommended about create it.
oracle-12c index-tuning
oracle-12c index-tuning
asked 13 mins ago
WindyWindy
1
New contributor
Windy is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 13 mins ago
WindyWindy
1
New contributor
Windy is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 13 mins ago
WindyWindy
1
New contributor
Windy is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
asked 13 mins ago
WindyWindy
1
asked 13 mins ago
WindyWindy
1
1
New contributor
Windy is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
New contributor
Windy is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
Windy is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.
add a comment |
add a comment |
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