I am looking up which exchange services which telephone numbers, from a table of fragmentary numbers that show which exchange services them. So my table contains, for example:
id |exchcode |exchname |easting|northin|leadin |
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12122 |SNL/UC |SANDAL |43430 |41306 |1924240 |
12123 |SNL/UC |SANDAL |43430 |41306 |1924241 |
881 |SNL/UD |SANDAL |43430 |41306 |1924249 |
2456 |BD/BCC/1 |BRADFORD CABLE |41627 |43262 |192421 |
4313 |NEY/UB |NORMANTON |43847 |42289 |192422 |
12124 |SNL/UC |SANDAL |43430 |41306 |192425 |
9949 |OBE/UB |HORBURY OSSETT |42857 |41971 |192428 |
9987 |OBE/UB |WAKEFIELD |42857 |41971 |1924 |
(Üzgünüm, biraz çöp biçimlendirme)
leadin is the leading part of the phone number I have to match (stored as a VARCHAR, not a number)
And I am supplied with a phone number 1924283777 (not real) how do I query to get the best match from the above table (It should pick exchange id 9949), or do I deal with it in code after I've done the query (php)
tl; dr: sütun leadin değerleri için değişken uzunluk, uzun leadin daha bir dizi ile iyi bir maç istiyoruz.