Description
In theory, sql1 and sql2 should return the same result. However, sql1 return 0 while sql2 return 1.
SQL1:
SELECT f1 FROM (SELECT (t0.c0 % (-1| 1 )) AS f1 FROM t0) AS t WHERE (f1+1);
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SQL2:
SELECT f1 FROM (SELECT (t0.c0 % (-1| 1 )) AS f1, ((t0.c0 % (-1| 1 ))+1) IS TRUE AS flag FROM t0) AS t WHERE flag=1;
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How to repeat
DROP DATABASE IF EXISTS database0;
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CREATE DATABASE database0;
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USE database0;
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CREATE TABLE t0(c0 CHAR(100) PRIMARY KEY NOT NULL);
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INSERT INTO t0 VALUES (1);
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version
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SELECT version();
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+----------------+
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| version() |
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+----------------+
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| 11.4.0-MariaDB |
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+----------------+
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1 row in set (0.00 sec)
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SELECT f1 FROM (SELECT (t0.c0 % (-1| 1 )) AS f1 FROM t0) AS t WHERE (f1+1); --sql1
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+-------+
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| f1 |
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+-------+
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| 0 |
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+-------+
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SELECT f1 FROM (SELECT (t0.c0 % (-1| 1 )) AS f1, ((t0.c0 % (-1| 1 ))+1) IS TRUE AS flag FROM t0) AS t WHERE flag=1; --sql2
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+-----------+
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| f1 |
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+-----------+
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| 1 |
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+-----------+
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