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POSQL Query too slow even "Using Index" on EXPLAIN
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copied!<p>i am trying to get all subscribers of a user</p> <p>my query:</p> <pre><code>SELECT COUNT(sub.id) as ids FROM subscribers as sub WHERE suid=541839243781 </code></pre> <p>EXPLAIN prints:</p> <pre> ╔════╦═════════════╦═══════╦══════╦═══════════════╦═════╦═════════╦═══════╦═══════╦═════════════╗ ║ id ║ select_type ║ table ║ type ║ possible_keys ║ key ║ key_len ║ ref ║ rows ║ Extra ║ ╠════╬═════════════╬═══════╬══════╬═══════════════╬═════╬═════════╬═══════╬═══════╬═════════════╣ ║ 1 ║ SIMPLE ║ sub ║ ref ║ i3 ║ i3 ║ 8 ║ const ║ 47890 ║ Using index ║ ╚════╩═════════════╩═══════╩══════╩═══════════════╩═════╩═════════╩═══════╩═══════╩═════════════╝ </pre> <p>so at the moment the total count i get is around <code>48k</code> and it takes <code>0.0333</code> to load... what if this goes up to <code>1m</code> or <code>5m</code> ?? then it could take ages to load up...</p> <p>my indexes on subscribers table are:</p> <pre> ╔═════════════╦════════════╦═══════════════════╦══════════════╦═════════════╦═══════════╦═════════════╦══════════╦════════╦══════╦════════════╦═════════╗ ║ Table ║ Non_unique ║ Key_name ║ Seq_in_index ║ Column_name ║ Collation ║ Cardinality ║ Sub_part ║ Packed ║ Null ║ Index_type ║ Comment ║ ╠═════════════╬════════════╬═══════════════════╬══════════════╬═════════════╬═══════════╬═════════════╬══════════╬════════╬══════╬════════════╬═════════╣ ║ subscribers ║ 0 ║ PRIMARY ║ 1 ║ id ║ A ║ 60251 ║ NULL ║ NULL ║ ║ BTREE ║ ║ ║ subscribers ║ 1 ║ total_subscribers ║ 1 ║ id ║ A ║ 60251 ║ NULL ║ NULL ║ ║ BTREE ║ ║ ║ subscribers ║ 1 ║ total_subscribers ║ 2 ║ suid ║ A ║ 60251 ║ NULL ║ NULL ║ ║ BTREE ║ ║ ║ subscribers ║ 1 ║ i3 ║ 1 ║ suid ║ A ║ 6025 ║ NULL ║ NULL ║ ║ BTREE ║ ║ ║ subscribers ║ 1 ║ i3 ║ 2 ║ uid ║ A ║ 60251 ║ NULL ║ NULL ║ ║ BTREE ║ ║ ║ subscribers ║ 1 ║ i3 ║ 3 ║ id ║ A ║ 60251 ║ NULL ║ NULL ║ ║ BTREE ║ ║ ╚═════════════╩════════════╩═══════════════════╩══════════════╩═════════════╩═══════════╩═════════════╩══════════╩════════╩══════╩════════════╩═════════╝ </pre> <p>so how can i make this query more efficient?</p>

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