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Add comparison operators and btree indexing support for type bytea.
From Joe Conway.
This commit is contained in:
Tom Lane
parent
4d7af98759
commit
95f8901a96
@ -15,7 +15,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/selfuncs.c,v 1.95 2001/07/16 05:06:59 tgl Exp $
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/selfuncs.c,v 1.96 2001/08/13 18:45:35 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -134,8 +134,16 @@ static void convert_string_to_scalar(unsigned char *value,
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double *scaledlobound,
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unsigned char *hibound,
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double *scaledhibound);
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static void convert_bytea_to_scalar(Datum value,
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double *scaledvalue,
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Datum lobound,
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double *scaledlobound,
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Datum hibound,
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double *scaledhibound);
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static double convert_one_string_to_scalar(unsigned char *value,
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int rangelo, int rangehi);
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static double convert_one_bytea_to_scalar(unsigned char *value, int valuelen,
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int rangelo, int rangehi);
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static unsigned char *convert_string_datum(Datum value, Oid typid);
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static double convert_timevalue_to_scalar(Datum value, Oid typid);
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static double get_att_numdistinct(Query *root, Var *var,
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@ -1664,6 +1672,9 @@ icnlikejoinsel(PG_FUNCTION_ARGS)
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* which is explained below. The reason why this routine deals with
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* three values at a time, not just one, is that we need it for strings.
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*
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* The bytea datatype is just enough different from strings that it has
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* to be treated separately.
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*
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* The several datatypes representing absolute times are all converted
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* to Timestamp, which is actually a double, and then we just use that
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* double value. Note this will give bad results for the various "special"
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@ -1718,6 +1729,17 @@ convert_to_scalar(Datum value, Oid valuetypid, double *scaledvalue,
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return true;
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}
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/*
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* Built-in bytea type
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*/
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case BYTEAOID:
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{
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convert_bytea_to_scalar(value, scaledvalue,
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lobound, scaledlobound,
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hibound, scaledhibound);
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return true;
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}
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/*
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* Built-in time types
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*/
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@ -1996,6 +2018,99 @@ convert_string_datum(Datum value, Oid typid)
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return (unsigned char *) val;
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}
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/*
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* Do convert_to_scalar()'s work for any bytea data type.
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*
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* Very similar to convert_string_to_scalar except we can't assume
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* null-termination and therefore pass explicit lengths around.
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*
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* Also, assumptions about likely "normal" ranges of characters have been
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* removed - a data range of 0..255 is always used, for now. (Perhaps
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* someday we will add information about actual byte data range to
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* pg_statistic.)
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*/
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static void
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convert_bytea_to_scalar(Datum value,
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double *scaledvalue,
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Datum lobound,
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double *scaledlobound,
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Datum hibound,
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double *scaledhibound)
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{
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int rangelo,
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rangehi,
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valuelen = VARSIZE(DatumGetPointer(value)) - VARHDRSZ,
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loboundlen = VARSIZE(DatumGetPointer(lobound)) - VARHDRSZ,
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hiboundlen = VARSIZE(DatumGetPointer(hibound)) - VARHDRSZ,
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i,
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minlen;
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unsigned char *valstr = (unsigned char *) VARDATA(DatumGetPointer(value)),
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*lostr = (unsigned char *) VARDATA(DatumGetPointer(lobound)),
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*histr = (unsigned char *) VARDATA(DatumGetPointer(hibound));
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/*
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* Assume bytea data is uniformly distributed across all byte values.
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*/
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rangelo = 0;
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rangehi = 255;
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/*
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* Now strip any common prefix of the three strings.
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*/
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minlen = Min(Min(valuelen, loboundlen), hiboundlen);
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for (i = 0; i < minlen; i++)
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{
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if (*lostr != *histr || *lostr != *valstr)
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break;
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lostr++, histr++, valstr++;
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loboundlen--, hiboundlen--, valuelen--;
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}
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/*
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* Now we can do the conversions.
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*/
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*scaledvalue = convert_one_bytea_to_scalar(valstr, valuelen, rangelo, rangehi);
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*scaledlobound = convert_one_bytea_to_scalar(lostr, loboundlen, rangelo, rangehi);
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*scaledhibound = convert_one_bytea_to_scalar(histr, hiboundlen, rangelo, rangehi);
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}
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static double
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convert_one_bytea_to_scalar(unsigned char *value, int valuelen,
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int rangelo, int rangehi)
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{
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double num,
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denom,
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base;
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if (valuelen <= 0)
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return 0.0; /* empty string has scalar value 0 */
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/*
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* Since base is 256, need not consider more than about 10
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* chars (even this many seems like overkill)
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*/
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if (valuelen > 10)
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valuelen = 10;
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/* Convert initial characters to fraction */
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base = rangehi - rangelo + 1;
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num = 0.0;
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denom = base;
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while (valuelen-- > 0)
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{
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int ch = *value++;
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if (ch < rangelo)
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ch = rangelo - 1;
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else if (ch > rangehi)
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ch = rangehi + 1;
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num += ((double) (ch - rangelo)) / denom;
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denom *= base;
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}
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return num;
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}
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/*
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* Do convert_to_scalar()'s work for any timevalue data type.
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*/
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@ -8,7 +8,7 @@
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*
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*
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* IDENTIFICATION
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/varlena.c,v 1.70 2001/05/03 19:00:36 tgl Exp $
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* $Header: /cvsroot/pgsql/src/backend/utils/adt/varlena.c,v 1.71 2001/08/13 18:45:35 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -875,3 +875,162 @@ name_text(PG_FUNCTION_ARGS)
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PG_RETURN_TEXT_P(result);
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}
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/*****************************************************************************
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* Comparison Functions used for bytea
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*
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* Note: btree indexes need these routines not to leak memory; therefore,
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* be careful to free working copies of toasted datums. Most places don't
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* need to be so careful.
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*****************************************************************************/
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Datum
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byteaeq(PG_FUNCTION_ARGS)
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{
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bytea *arg1 = PG_GETARG_BYTEA_P(0);
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bytea *arg2 = PG_GETARG_BYTEA_P(1);
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int len1,
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len2;
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bool result;
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len1 = VARSIZE(arg1) - VARHDRSZ;
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len2 = VARSIZE(arg2) - VARHDRSZ;
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/* fast path for different-length inputs */
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if (len1 != len2)
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result = false;
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else
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result = (memcmp(VARDATA(arg1), VARDATA(arg2), len1) == 0);
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PG_FREE_IF_COPY(arg1, 0);
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PG_FREE_IF_COPY(arg2, 1);
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PG_RETURN_BOOL(result);
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}
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Datum
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byteane(PG_FUNCTION_ARGS)
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{
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bytea *arg1 = PG_GETARG_BYTEA_P(0);
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bytea *arg2 = PG_GETARG_BYTEA_P(1);
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int len1,
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len2;
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bool result;
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len1 = VARSIZE(arg1) - VARHDRSZ;
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len2 = VARSIZE(arg2) - VARHDRSZ;
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/* fast path for different-length inputs */
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if (len1 != len2)
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result = true;
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else
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result = (memcmp(VARDATA(arg1), VARDATA(arg2), len1) != 0);
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PG_FREE_IF_COPY(arg1, 0);
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PG_FREE_IF_COPY(arg2, 1);
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PG_RETURN_BOOL(result);
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}
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Datum
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bytealt(PG_FUNCTION_ARGS)
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{
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bytea *arg1 = PG_GETARG_BYTEA_P(0);
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bytea *arg2 = PG_GETARG_BYTEA_P(1);
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int len1,
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len2;
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int cmp;
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len1 = VARSIZE(arg1) - VARHDRSZ;
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len2 = VARSIZE(arg2) - VARHDRSZ;
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cmp = memcmp(VARDATA(arg1), VARDATA(arg2), Min(len1, len2));
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PG_FREE_IF_COPY(arg1, 0);
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PG_FREE_IF_COPY(arg2, 1);
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PG_RETURN_BOOL((cmp < 0) || ((cmp == 0) && (len1 < len2)));
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}
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Datum
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byteale(PG_FUNCTION_ARGS)
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{
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bytea *arg1 = PG_GETARG_BYTEA_P(0);
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bytea *arg2 = PG_GETARG_BYTEA_P(1);
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int len1,
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len2;
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int cmp;
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len1 = VARSIZE(arg1) - VARHDRSZ;
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len2 = VARSIZE(arg2) - VARHDRSZ;
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cmp = memcmp(VARDATA(arg1), VARDATA(arg2), Min(len1, len2));
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PG_FREE_IF_COPY(arg1, 0);
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PG_FREE_IF_COPY(arg2, 1);
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PG_RETURN_BOOL((cmp < 0) || ((cmp == 0) && (len1 <= len2)));
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}
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Datum
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byteagt(PG_FUNCTION_ARGS)
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{
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bytea *arg1 = PG_GETARG_BYTEA_P(0);
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bytea *arg2 = PG_GETARG_BYTEA_P(1);
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int len1,
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len2;
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int cmp;
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len1 = VARSIZE(arg1) - VARHDRSZ;
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len2 = VARSIZE(arg2) - VARHDRSZ;
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cmp = memcmp(VARDATA(arg1), VARDATA(arg2), Min(len1, len2));
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PG_FREE_IF_COPY(arg1, 0);
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PG_FREE_IF_COPY(arg2, 1);
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PG_RETURN_BOOL((cmp > 0) || ((cmp == 0) && (len1 > len2)));
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}
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Datum
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byteage(PG_FUNCTION_ARGS)
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{
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bytea *arg1 = PG_GETARG_BYTEA_P(0);
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bytea *arg2 = PG_GETARG_BYTEA_P(1);
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int len1,
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len2;
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int cmp;
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len1 = VARSIZE(arg1) - VARHDRSZ;
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len2 = VARSIZE(arg2) - VARHDRSZ;
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cmp = memcmp(VARDATA(arg1), VARDATA(arg2), Min(len1, len2));
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PG_FREE_IF_COPY(arg1, 0);
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PG_FREE_IF_COPY(arg2, 1);
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PG_RETURN_BOOL((cmp > 0) || ((cmp == 0) && (len1 >= len2)));
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}
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Datum
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byteacmp(PG_FUNCTION_ARGS)
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{
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bytea *arg1 = PG_GETARG_BYTEA_P(0);
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bytea *arg2 = PG_GETARG_BYTEA_P(1);
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int len1,
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len2;
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int cmp;
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len1 = VARSIZE(arg1) - VARHDRSZ;
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len2 = VARSIZE(arg2) - VARHDRSZ;
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cmp = memcmp(VARDATA(arg1), VARDATA(arg2), Min(len1, len2));
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if ((cmp == 0) && (len1 != len2))
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cmp = (len1 < len2) ? -1 : 1;
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PG_FREE_IF_COPY(arg1, 0);
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PG_FREE_IF_COPY(arg2, 1);
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PG_RETURN_INT32(cmp);
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}
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@ -37,7 +37,7 @@
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* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* $Id: catversion.h,v 1.87 2001/08/10 18:57:39 tgl Exp $
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* $Id: catversion.h,v 1.88 2001/08/13 18:45:36 tgl Exp $
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*
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*-------------------------------------------------------------------------
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*/
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@ -53,6 +53,6 @@
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*/
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/* yyyymmddN */
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#define CATALOG_VERSION_NO 200108101
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#define CATALOG_VERSION_NO 200108131
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#endif
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@ -8,7 +8,7 @@
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* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* $Id: pg_amop.h,v 1.39 2001/08/10 18:57:39 tgl Exp $
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* $Id: pg_amop.h,v 1.40 2001/08/13 18:45:36 tgl Exp $
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*
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* NOTES
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* the genbki.sh script reads this file and generates .bki
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@ -249,6 +249,16 @@ DATA(insert ( 403 1077 1062 3 ));
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DATA(insert ( 403 1077 1069 4 ));
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DATA(insert ( 403 1077 1068 5 ));
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/*
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* nbtree bytea_ops
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*/
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DATA(insert ( 403 1961 1957 1 ));
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DATA(insert ( 403 1961 1958 2 ));
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DATA(insert ( 403 1961 1955 3 ));
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DATA(insert ( 403 1961 1960 4 ));
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DATA(insert ( 403 1961 1959 5 ));
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/*
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* nbtree date_ops
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*/
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@ -10,7 +10,7 @@
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* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* $Id: pg_amproc.h,v 1.28 2001/08/10 18:57:39 tgl Exp $
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* $Id: pg_amproc.h,v 1.29 2001/08/13 18:45:36 tgl Exp $
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*
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* NOTES
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* the genbki.sh script reads this file and generates .bki
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@ -101,6 +101,7 @@ DATA(insert (403 1690 1693 1));
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DATA(insert (403 1399 1358 1));
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DATA(insert (403 424 1596 1));
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DATA(insert (403 425 1672 1));
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DATA(insert (403 1961 1954 1));
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/* hash */
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@ -8,7 +8,7 @@
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* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* $Id: pg_opclass.h,v 1.37 2001/01/24 19:43:21 momjian Exp $
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* $Id: pg_opclass.h,v 1.38 2001/08/13 18:45:36 tgl Exp $
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*
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* NOTES
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* the genbki.sh script reads this file and generates .bki
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@ -123,5 +123,7 @@ DATA(insert OID = 424 ( bit_ops 1560 ));
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DESCR("");
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DATA(insert OID = 425 ( varbit_ops 1562 ));
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DESCR("");
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DATA(insert OID = 1961 ( bytea_ops 17 ));
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DESCR("");
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#endif /* PG_OPCLASS_H */
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@ -8,7 +8,7 @@
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* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* $Id: pg_operator.h,v 1.91 2001/06/17 02:05:20 tgl Exp $
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* $Id: pg_operator.h,v 1.92 2001/08/13 18:45:36 tgl Exp $
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*
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* NOTES
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* the genbki.sh script reads this file and generates .bki
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@ -809,6 +809,14 @@ DATA(insert OID = 1919 ( "+" PGUID 0 l t f 0 700 700 0 0 0 0 float4
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DATA(insert OID = 1920 ( "+" PGUID 0 l t f 0 701 701 0 0 0 0 float8up - - ));
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DATA(insert OID = 1921 ( "+" PGUID 0 l t f 0 1700 1700 0 0 0 0 numeric_uplus - - ));
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/* bytea operators */
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DATA(insert OID = 1955 ( "=" PGUID 0 b t t 17 17 16 1955 1956 1957 1957 byteaeq eqsel eqjoinsel ));
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DATA(insert OID = 1956 ( "<>" PGUID 0 b t f 17 17 16 1956 1955 0 0 byteane neqsel neqjoinsel ));
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DATA(insert OID = 1957 ( "<" PGUID 0 b t f 17 17 16 1959 1960 0 0 bytealt scalarltsel scalarltjoinsel ));
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DATA(insert OID = 1958 ( "<=" PGUID 0 b t f 17 17 16 1960 1959 0 0 byteale scalarltsel scalarltjoinsel ));
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DATA(insert OID = 1959 ( ">" PGUID 0 b t f 17 17 16 1957 1958 0 0 byteagt scalargtsel scalargtjoinsel ));
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DATA(insert OID = 1960 ( ">=" PGUID 0 b t f 17 17 16 1958 1957 0 0 byteage scalargtsel scalargtjoinsel ));
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/*
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* function prototypes
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*/
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@ -7,7 +7,7 @@
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* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
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* Portions Copyright (c) 1994, Regents of the University of California
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*
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* $Id: pg_proc.h,v 1.202 2001/08/10 20:52:25 tgl Exp $
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* $Id: pg_proc.h,v 1.203 2001/08/13 18:45:36 tgl Exp $
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*
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* NOTES
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* The script catalog/genbki.sh reads this file and generates .bki
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@ -2699,6 +2699,22 @@ DATA(insert OID = 1946 ( encode PGUID 12 f t t t 2 f 25 "17 25" 100 0 0 10
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DESCR("Convert bytea value into some ascii-only text string");
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DATA(insert OID = 1947 ( decode PGUID 12 f t t t 2 f 17 "25 25" 100 0 0 100 binary_decode - ));
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DESCR("Convert ascii-encoded text string into bytea value");
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DATA(insert OID = 1948 ( byteaeq PGUID 12 f t t t 2 f 16 "17 17" 100 0 0 100 byteaeq - ));
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||||
DESCR("equal");
|
||||
DATA(insert OID = 1949 ( bytealt PGUID 12 f t t t 2 f 16 "17 17" 100 0 0 100 bytealt - ));
|
||||
DESCR("less-than");
|
||||
DATA(insert OID = 1950 ( byteale PGUID 12 f t t t 2 f 16 "17 17" 100 0 0 100 byteale - ));
|
||||
DESCR("less-than-or-equal");
|
||||
DATA(insert OID = 1951 ( byteagt PGUID 12 f t t t 2 f 16 "17 17" 100 0 0 100 byteagt - ));
|
||||
DESCR("greater-than");
|
||||
DATA(insert OID = 1952 ( byteage PGUID 12 f t t t 2 f 16 "17 17" 100 0 0 100 byteage - ));
|
||||
DESCR("greater-than-or-equal");
|
||||
DATA(insert OID = 1953 ( byteane PGUID 12 f t t t 2 f 16 "17 17" 100 0 0 100 byteane - ));
|
||||
DESCR("not equal");
|
||||
DATA(insert OID = 1954 ( byteacmp PGUID 12 f t t t 2 f 23 "17 17" 100 0 0 100 byteacmp - ));
|
||||
DESCR("less-equal-greater");
|
||||
|
||||
|
||||
/*
|
||||
* prototypes for functions pg_proc.c
|
||||
|
||||
@ -7,7 +7,7 @@
|
||||
* Portions Copyright (c) 1996-2001, PostgreSQL Global Development Group
|
||||
* Portions Copyright (c) 1994, Regents of the University of California
|
||||
*
|
||||
* $Id: builtins.h,v 1.159 2001/08/09 18:28:18 petere Exp $
|
||||
* $Id: builtins.h,v 1.160 2001/08/13 18:45:36 tgl Exp $
|
||||
*
|
||||
*-------------------------------------------------------------------------
|
||||
*/
|
||||
@ -412,6 +412,13 @@ extern Datum byteaSetByte(PG_FUNCTION_ARGS);
|
||||
extern Datum byteaSetBit(PG_FUNCTION_ARGS);
|
||||
extern Datum binary_encode(PG_FUNCTION_ARGS);
|
||||
extern Datum binary_decode(PG_FUNCTION_ARGS);
|
||||
extern Datum byteaeq(PG_FUNCTION_ARGS);
|
||||
extern Datum byteane(PG_FUNCTION_ARGS);
|
||||
extern Datum bytealt(PG_FUNCTION_ARGS);
|
||||
extern Datum byteale(PG_FUNCTION_ARGS);
|
||||
extern Datum byteagt(PG_FUNCTION_ARGS);
|
||||
extern Datum byteage(PG_FUNCTION_ARGS);
|
||||
extern Datum byteacmp(PG_FUNCTION_ARGS);
|
||||
|
||||
/* version.c */
|
||||
extern Datum pgsql_version(PG_FUNCTION_ARGS);
|
||||
|
||||
Loading…
Reference in New Issue
Block a user