diff options
Diffstat (limited to 'myisam/mi_unique.c')
| -rw-r--r-- | myisam/mi_unique.c | 53 |
1 files changed, 30 insertions, 23 deletions
diff --git a/myisam/mi_unique.c b/myisam/mi_unique.c index ad685f4cbdc..c03182456df 100644 --- a/myisam/mi_unique.c +++ b/myisam/mi_unique.c @@ -93,7 +93,7 @@ ha_checksum mi_unique_hash(MI_UNIQUEDEF *def, const byte *record) } } pos= record+keyseg->start; - if (keyseg->flag & HA_VAR_LENGTH) + if (keyseg->flag & HA_VAR_LENGTH_PART) { uint tmp_length=uint2korr(pos); pos+=2; /* Skip VARCHAR length */ @@ -136,7 +136,8 @@ int mi_unique_comp(MI_UNIQUEDEF *def, const byte *a, const byte *b, for (keyseg=def->seg ; keyseg < def->end ; keyseg++) { enum ha_base_keytype type=(enum ha_base_keytype) keyseg->type; - uint length=keyseg->length; + uint a_length, b_length; + a_length= b_length= keyseg->length; /* If part is NULL it's regarded as different */ if (keyseg->null_bit) @@ -154,43 +155,49 @@ int mi_unique_comp(MI_UNIQUEDEF *def, const byte *a, const byte *b, } pos_a= a+keyseg->start; pos_b= b+keyseg->start; - if (keyseg->flag & HA_VAR_LENGTH) + if (keyseg->flag & HA_VAR_LENGTH_PART) { - uint tmp_length=uint2korr(pos_a); - if (tmp_length != uint2korr(pos_b)) - return 1; - pos_a+=2; /* Skip VARCHAR length */ - pos_b+=2; - set_if_smaller(length,tmp_length); + a_length= uint2korr(pos_a); + b_length= uint2korr(pos_b); + pos_a+= 2; /* Skip VARCHAR length */ + pos_b+= 2; + set_if_smaller(a_length, keyseg->length); + set_if_smaller(b_length, keyseg->length); } else if (keyseg->flag & HA_BLOB_PART) { - /* Only compare 'length' characters if length<> 0 */ - uint a_length= _mi_calc_blob_length(keyseg->bit_start,pos_a); - uint b_length= _mi_calc_blob_length(keyseg->bit_start,pos_b); + /* Only compare 'length' characters if length != 0 */ + a_length= _mi_calc_blob_length(keyseg->bit_start,pos_a); + b_length= _mi_calc_blob_length(keyseg->bit_start,pos_b); /* Check that a and b are of equal length */ - if (length && a_length > length) - a_length=length; - if (!length || length > b_length) - length=b_length; - if (length != a_length) - return 1; - /* Both strings are at least 'length' long */ + if (keyseg->length) + { + /* + This is used in some cases when we are not interested in comparing + the whole length of the blob. + */ + set_if_smaller(a_length, keyseg->length); + set_if_smaller(b_length, keyseg->length); + } memcpy_fixed((byte*) &pos_a,pos_a+keyseg->bit_start,sizeof(char*)); memcpy_fixed((byte*) &pos_b,pos_b+keyseg->bit_start,sizeof(char*)); } if (type == HA_KEYTYPE_TEXT || type == HA_KEYTYPE_VARTEXT) { - if (mi_compare_text(keyseg->charset, (uchar *) pos_a, length, - (uchar *) pos_b, length, 0, 0)) - return 1; + if (mi_compare_text(keyseg->charset, (uchar *) pos_a, a_length, + (uchar *) pos_b, b_length, 0, 1)) + return 1; } else { - end= pos_a+length; + if (a_length != b_length) + return 1; + end= pos_a+a_length; while (pos_a != end) + { if (*pos_a++ != *pos_b++) return 1; + } } } return 0; |