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the answer is: it depends.<br />
<br />
functionally, yes. however, technically, depending on the indexes you have on the tables, it will perform either a index-based row-lookup, a merge join, etc.<br />
<br />
run the explain plan for the query, and you will know.
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the answer is: it depends.

functionally, yes. however, technically, depending on the indexes you have on the tables, it will perform either a index-based row-lookup, a merge join, etc.

run the explain plan for the query, and you will know.

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I run the explain plan and reach the conclusion that oracle always perform cartesian product. I was suspicious about the result that why i need to verify. &nbsp;<br />
<br />
so question is if we dont have indexes and assume we are going by book then what will happen, will it perform the cartesian product ?
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I run the explain plan and reach the conclusion that oracle always perform cartesian product. I was suspicious about the result that why i need to verify.  

so question is if we dont have indexes and assume we are going by book then what will happen, will it perform the cartesian product ?

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yes.<br />
this is why indexes are crutial, the bigger the table, the more important they are.
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yes.
this is why indexes are crutial, the bigger the table, the more important they are.

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Hi guys<br />
<br />
Does the oracle always does the cartesian product before filtering out the records based on join condition <br />
<br />
For example <br />
&nbsp; &nbsp; &nbsp; select * from category_new, category_temp where <br />
&nbsp; &nbsp; &nbsp;category_new.category = category_temp.category <br />
<br />
what will happen in this case will the oracle behind the scene fetch all the records from both the tables, then perform cartesian product and then apply equi join.<br />
<br />
Is this the case that oracle will perform cartesian product each time we ask for join ?
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Hi guys

Does the oracle always does the cartesian product before filtering out the records based on join condition 

For example 
      select * from category_new, category_temp where 
     category_new.category = category_temp.category 

what will happen in this case will the oracle behind the scene fetch all the records from both the tables, then perform cartesian product and then apply equi join.

Is this the case that oracle will perform cartesian product each time we ask for join ?

does Cartesian product happens each time we execute joins

Oracle is an object-relational database management system. It supports a large number of languages and application development frameworks. Its primary languages are SQL, PL/SQL and Java, but it also includes support for C and C++. Oracle also has its own enterprise modules and application server software.