Oracle DB automatically collects statistics to optimize performance of queries, but you can manually call 'ANALYZE' command to start collecting statistics immediately which may improve performance. For example

ANALYZE INDEX JCR_PK_SITEM COMPUTE STATISTICS
ANALYZE INDEX JCR_IDX_SITEM_PARENT_FK COMPUTE STATISTICS
ANALYZE INDEX JCR_IDX_SITEM_PARENT COMPUTE STATISTICS
ANALYZE INDEX JCR_IDX_SITEM_PARENT_NAME COMPUTE STATISTICS
ANALYZE INDEX JCR_IDX_SITEM_PARENT_ID COMPUTE STATISTICS
ANALYZE INDEX JCR_PK_SVALUE COMPUTE STATISTICS
ANALYZE INDEX JCR_IDX_SVALUE_PROPERTY COMPUTE STATISTICS
ANALYZE INDEX JCR_PK_SREF COMPUTE STATISTICS
ANALYZE INDEX JCR_IDX_SREF_PROPERTY COMPUTE STATISTICS
ANALYZE INDEX JCR_PK_SCONTAINER COMPUTE STATISTICS