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author | Tom Lane <tgl@sss.pgh.pa.us> | 2011-01-09 15:24:22 -0500 |
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committer | Tom Lane <tgl@sss.pgh.pa.us> | 2011-01-09 15:25:17 -0500 |
commit | 327b25768217f5d4fd82770d0ab449814548f094 (patch) | |
tree | 6db4cd82153e05fd89c25c94c12df6c0ea7d03f4 /contrib/btree_gin | |
parent | 4448917d51d6f87655ce357cca009634b0a136e4 (diff) | |
download | postgresql-327b25768217f5d4fd82770d0ab449814548f094.tar.gz |
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Diffstat (limited to 'contrib/btree_gin')
-rw-r--r-- | contrib/btree_gin/btree_gin.c | 9 |
1 files changed, 5 insertions, 4 deletions
diff --git a/contrib/btree_gin/btree_gin.c b/contrib/btree_gin/btree_gin.c index f8fae18eaf..486a662c78 100644 --- a/contrib/btree_gin/btree_gin.c +++ b/contrib/btree_gin/btree_gin.c @@ -394,10 +394,11 @@ static TypeInfo TypeInfo_varbit = {true, leftmostvalue_varbit, bitcmp}; GIN_SUPPORT(varbit) /* - * Numeric type hasn't applicable left-most value, so NULL - * is used for that. NULL will never be an argument for a C-level - * numeric function except gin_numeric_cmp and it will not be stored - * somewhere and it could not be returned in any user SQL query. + * Numeric type hasn't a real left-most value, so we use PointerGetDatum(NULL) + * (*not* a SQL NULL) to represent that. We can get away with that because + * the value returned by our leftmostvalue function will never be stored in + * the index nor passed to anything except our compare and prefix-comparison + * functions. The same trick could be used for other pass-by-reference types. */ #define NUMERIC_IS_LEFTMOST(x) ((x) == NULL) |