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page0cur.c:

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Prepare for 5.x where HA_READ_PREFIX_LAST may pass only a few first bytes of the last field in a key value
ha_innodb.cc:
  In 4.0 always assume HA_READ_PREFIX_LAST passes a complete-field prefix of a key value; LIKE queries use a padding trick


sql/ha_innodb.cc:
  In 4.0 always assume HA_READ_PREFIX_LAST passes a complete-field prefix of a key value; LIKE queries use a padding trick
innobase/page/page0cur.c:
  Prepare for 5.x where HA_READ_PREFIX_LAST may pass only a few first bytes of the last field in a key value
This commit is contained in:
unknown 2003-02-18 19:43:41 +02:00
commit b3fa1d867f
2 changed files with 53 additions and 22 deletions
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71
innobase/page/page0cur.c
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@ -120,6 +120,53 @@ page_cur_try_search_shortcut(
#endif
/********************************************************************
Checks if the nth field in a record is a character type field which extends
the nth field in tuple, i.e., the field is longer or equal in length and has
common first characters. */
static
ibool
page_cur_rec_field_extends(
/*=======================*/
/* out: TRUE if rec field extends tuple
field */
dtuple_t* tuple, /* in: data tuple */
rec_t* rec, /* in: record */
ulint n) /* in: compare nth field */
{
dtype_t* type;
dfield_t* dfield;
byte* rec_f;
ulint rec_f_len;
dfield = dtuple_get_nth_field(tuple, n);
type = dfield_get_type(dfield);
rec_f = rec_get_nth_field(rec, n, &rec_f_len);
if (type->mtype == DATA_VARCHAR
|| type->mtype == DATA_CHAR
|| type->mtype == DATA_FIXBINARY
|| type->mtype == DATA_BINARY
|| type->mtype == DATA_BLOB
|| type->mtype == DATA_VARMYSQL
|| type->mtype == DATA_MYSQL) {
if (dfield_get_len(dfield) != UNIV_SQL_NULL
&& rec_f_len != UNIV_SQL_NULL
&& rec_f_len >= dfield_get_len(dfield)
&& 0 == cmp_data_data_slow(type, dfield_get_data(dfield),
dfield_get_len(dfield),
rec_f, dfield_get_len(dfield))) {
return(TRUE);
}
}
return(FALSE);
}
/********************************************************************
Searches the right position for a page cursor. */
@ -239,16 +286,8 @@ page_cur_search_with_match(
} else if (cmp == -1) {
if (mode == PAGE_CUR_LE_OR_EXTENDS
&& dfield_get_len(dtuple_get_nth_field(tuple,
cur_matched_fields))
== cur_matched_bytes
&& rec_get_nth_field_len(mid_rec,
cur_matched_fields)
!= UNIV_SQL_NULL) {
/* This means current dfield is not SQL
NULL, and the current rec field extends it */
&& page_cur_rec_field_extends(tuple, mid_rec,
cur_matched_fields)) {
low = mid;
low_matched_fields = cur_matched_fields;
low_matched_bytes = cur_matched_bytes;
@ -296,16 +335,8 @@ page_cur_search_with_match(
} else if (cmp == -1) {
if (mode == PAGE_CUR_LE_OR_EXTENDS
&& dfield_get_len(dtuple_get_nth_field(tuple,
cur_matched_fields))
== cur_matched_bytes
&& rec_get_nth_field_len(mid_rec,
cur_matched_fields)
!= UNIV_SQL_NULL) {
/* This means current dfield is not SQL
NULL, and the current rec field extends it */
&& page_cur_rec_field_extends(tuple, mid_rec,
cur_matched_fields)) {
low_rec = mid_rec;
low_matched_fields = cur_matched_fields;
low_matched_bytes = cur_matched_bytes;