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  Undocumented Oracle hints

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Undocumented hints
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Undocumented hints

With hints one can influence the optimizer. The usage of hints (with exception of the RULE-hint) causes Oracle to use the Cost Based optimizer.

The following syntax is used for hints:

select /*+ HINT */ name
from emp
where id =1;

Where HINT is replaced by the hint text. The following hints are undocumented:
See Oracle hints for documented hints.

BYPASS_RECURSIVE_CHECK
BYPASS_UJVC
CACHE_CB
CACHE_TEMP_TABLE
CIV_GB
COLLECTIONS_GET_REFS
CUBE_GB
CURSOR_SHARING_EXACT
DEREF_NO_REWRITE
DML_UPDATE
DOMAIN_INDEX_NO_SORT
DOMAIN_INDEX_SORT
DYNAMIC_SAMPLING
DYNAMIC_SAMPLING_EST_CDN
EXPAND_GSET_TO_UNION
FORCE_SAMPLE_BLOCK
GBY_CONC_ROLLUP
GLOBAL_TABLE_HINTS
HWM_BROKERED
IGNORE_ON_CLAUSE
IGNORE_WHERE_CLAUSE
INDEX_RRS
INDEX_SS
INDEX_SS_ASC
INDEX_SS_DESC
LIKE_EXPAND
LOCAL_INDEXES
MV_MERGE
NESTED_TABLE_GET_REFS
NESTED_TABLE_SET_REFS
NESTED_TABLE_SET_SETID
NO_EXPAND_GSET_TO_UNION
NO_FACT
NO_FILTERING
NO_ORDER_ROLLUPS
NO_PRUNE_GSETS
NO_STATS_GSETS
NO_UNNEST
NOCPU_COSTING
OVERFLOW_NOMOVE
PIV_GB
PIV_SSF
PQ_MAP
PQ_NOMAP
REMOTE_MAPPED
RESTORE_AS_INTERVALS
SAVE_AS_INTERVALS
SCN_ASCENDING
SKIP_EXT_OPTIMIZER
SQLLDR
SYS_DL_CURSOR
SYS_PARALLEL_TXN
SYS_RID_ORDER
TIV_GB
TIV_SSF
UNNEST
USE_TTT_FOR_GSETS