for example, I now have a sql query
for example
but I also want to know what the data type of apply_date is
what to do?
for example, I now have a sql query
for example
but I also want to know what the data type of apply_date is
what to do?
use views? But I don't know if it's necessary to create a view
create a view
mysql > create view t (id,score) as select id,score from grade;
Query OK, 0 rows affected (0.02 sec)
View the types of fields in the view
2 rows in set (0.00 sec)
if you use java jdbc, you can get the field type through metadata
ResultSet rs = stmt.executeQuery("SELECT a, b, c FROM TABLE2");//,
ResultSetMetaData rsmd = rs.getMetaData();
int numberOfColumns = rsmd.getColumnCount(); //
structure in ResultSetMetaData:
om.mysql.jdbc.ResultSetMetaData@132e13d - Field level information:
com.mysql.jdbc.Field@1617189[catalog=test,tableName=MyBean,originalTableName=mybean,columnName=id,originalColumnName=id,mysqlType=3(FIELD_TYPE_LONG),flags= PRIMARY_KEY, charsetIndex=63, charsetName=US-ASCII]
com.mysql.jdbc.Field@64f6cd[catalog=test,tableName=MyBean,originalTableName=mybean,columnName=name,originalColumnName=name,mysqlType=253(FIELD_TYPE_VAR_STRING),flags=, charsetIndex=8, charsetName=Cp1252]$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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