for example, there are three tables below
t1ridt2t3
try the following statement
SELECT
t1.rid,
t1.col1,
t2.col2,
t3.col3
FROM
t1
LEFT JOIN t2 ON t1.rid = t2.rid
LEFT JOIN t3 ON t1.rid = t3.ridwill get the result of rid=3. How should I write this SQL
? add a condition where not (t2.col2 is null and t3.col3 is null)
$selectTip = $pdo->query("SELECT * FROM `tips_rate` WHERE `tip_id` = ".$row[ id ]." " ); $selecttotal = mysqli_num_rows($selectTip); $rate = $pdo->query("SELEC...
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like this SELECT * FROM material WHERE {key:value} limit 1 ...
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Table structure ...
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ask God to help me translate this native SQL statement into TP5 thank you! It is Db:: ( name )-> this kind of chained operation select a.id, a.titlerect a. Createwriting time as answer_count from fa_question a. Isometric solvepaper count (b.qid) as ...