FLOAT型にCASTする
MySQLのCAST()はFLOATは指定できない
FLOATの代わりにDECILAML()を指定する
MySQL> SELECT CAST(123 AS DECIMAL(10,2));
+----------------------------+
| CAST(123 AS DECIMAL(10,2)) |
+----------------------------+
| 123.00 |
+----------------------------+
DECIMAL()の引数について
MySQL> SELECT CAST(123 AS DECIMAL(10,2));
+----------------------------+
| CAST(123 AS DECIMAL(10,2)) |
+----------------------------+
| 123.00 |
+----------------------------+
MySQL> SELECT CAST(123 AS DECIMAL(3,2));
+---------------------------+
| CAST(123 AS DECIMAL(3,2)) |
+---------------------------+
| 9.99 |
+---------------------------+