[英]Increase mysql query with sub-query performance
嗨,我有這樣的查詢,如果我執行它需要大約 15 秒,我該如何優化查詢?
SELECT
tr.id_igd,
tr.rm,
mpa.nama as nm_pasien,
mpa.no_tlp_pasien as telp_pasien,
mpa.rating,
(SELECT d.nama FROM m_pegawai d WHERE d.nip = dokter) AS dokter,
tr.status_pasien,
tr.kunjungan,
tr.tgl_checkup,
tr.tgl_keluar
FROM
t_igd tr
INNER JOIN m_pasien mpa ON mpa.no_rm = tr.rm
我的意思是可以將子查詢更改為多一個 JOIN:
SELECT
tr.id_igd,
tr.rm,
mpa.nama as nm_pasien,
mpa.no_tlp_pasien as telp_pasien,
mpa.rating,
d.nama AS dokter,
tr.status_pasien,
tr.kunjungan,
tr.tgl_checkup,
tr.tgl_keluar
FROM
t_igd tr
INNER JOIN m_pasien mpa ON mpa.no_rm = tr.rm
LEFT JOIN m_pegawai d ON d.nip = dokter;
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