一个坑:java.sql.ResultSet.getInt==》the column value; if the value is SQL NULL, the value returned is 0

简介: Retrieves the value of the designated column in the current row of this ResultSet object as a String in the Java programming language.

Retrieves the value of the designated column in the current row of this ResultSet object as a String in the Java programming language.

Parameters:
columnLabel the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
the column value; if the value is SQL NULL, the value returned is null
Throws:
SQLException - if the columnLabel is not valid; if a database access error occurs or this method is called on a closed result set
 

int java.sql.ResultSet.getInt(String columnLabel) throws SQLException

Retrieves the value of the designated column in the current row of this ResultSet object as an int in the Java programming language.

Parameters:
columnLabel the label for the column specified with the SQL AS clause. If the SQL AS clause was not specified, then the label is the name of the column
Returns:
the column value; if the value is SQL NULL, the value returned is 0
Throws:
 
 
 
 
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