Example usage for java.sql ParameterMetaData isNullable

Introduction

In this page you can find the example usage for java.sql ParameterMetaData isNullable.

Prototype

int isNullable(int param) throws SQLException;

Source Link

Document

Retrieves whether null values are allowed in the designated parameter.

Usage

From source file:Main.java

public static void main(String[] args) throws Exception {
    Connection conn = getHSQLConnection();
    System.out.println("Got Connection.");
    Statement st = conn.createStatement();
    st.executeUpdate("create table survey (id int,name varchar);");
    st.executeUpdate("create view surveyView as (select * from survey);");
    st.executeUpdate("insert into survey (id,name ) values (1,'nameValue')");

    PreparedStatement pstmt = null;
    ParameterMetaData paramMetaData = null;
    String query = "select * from survey where id > ? and name = ?";
    pstmt = conn.prepareStatement(query);
    paramMetaData = pstmt.getParameterMetaData();
    if (paramMetaData == null) {
        System.out.println("db vendor does NOT support ParameterMetaData");
    } else {/*w w w.  j av a 2  s . co m*/
        System.out.println("db vendor supports ParameterMetaData");
        // find out the number of dynamic parameters
        int paramCount = paramMetaData.getParameterCount();
        System.out.println("paramCount=" + paramCount);
        System.out.println("-------------------");
        for (int param = 1; param <= paramCount; param++) {
            System.out.println("param number=" + param);
            int nullable = paramMetaData.isNullable(param);
            if (nullable == ParameterMetaData.parameterNoNulls) {
                System.out.println("parameter will not allow NULL values.");
            } else if (nullable == ParameterMetaData.parameterNullable) {
                System.out.println("parameter will allow NULL values.");
            } else {
                System.out.println("nullability of a parameter is unknown.");
            }
        }
    }

    pstmt.close();
    conn.close();

}

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From source file:com.tesora.dve.db.mysql.MysqlNative.java

@Override
public ColumnMetadata getParameterColumnInfo(ParameterMetaData pmd, int colIdx) throws SQLException {
    ColumnMetadata out = new ColumnMetadata();
    out.setDataType(pmd.getParameterType(colIdx));
    out.setPrecision(pmd.getPrecision(colIdx));
    out.setScale(pmd.getScale(colIdx));/*from  w w  w.  j a  va2s. c  o m*/
    if (ParameterMetaData.parameterNullable == pmd.isNullable(colIdx))
        out.setNullable(Boolean.TRUE);
    out.setTypeName(NativeType.fixName(pmd.getParameterTypeName(colIdx)));
    return out;
}

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From source file:com.alibaba.wasp.jdbc.TestPreparedStatement.java

public void testParameterMetaData() throws SQLException {
    PreparedStatement prep = conn.prepareStatement("SELECT ?, ?, ? FROM DUAL");
    ParameterMetaData pm = prep.getParameterMetaData();
    assertEquals("java.lang.String", pm.getParameterClassName(1));
    assertEquals("VARCHAR", pm.getParameterTypeName(1));
    assertEquals(3, pm.getParameterCount());
    assertEquals(ParameterMetaData.parameterModeIn, pm.getParameterMode(1));
    assertEquals(Types.VARCHAR, pm.getParameterType(1));
    assertEquals(0, pm.getPrecision(1));
    assertEquals(0, pm.getScale(1));//from   w w  w .  j  a v  a2s .c om
    assertEquals(ResultSetMetaData.columnNullableUnknown, pm.isNullable(1));
    assertEquals(pm.isSigned(1), true);
    assertThrows(SQLErrorCode.INVALID_VALUE_2, pm).getPrecision(0);
    assertThrows(SQLErrorCode.INVALID_VALUE_2, pm).getPrecision(4);
    prep.close();
    assertThrows(SQLErrorCode.OBJECT_CLOSED, pm).getPrecision(1);

    Statement stat = conn.createStatement();
    stat.execute("CREATE TABLE TEST3(ID INT, NAME VARCHAR(255), DATA DECIMAL(10,2))");
    PreparedStatement prep1 = conn.prepareStatement("UPDATE TEST3 SET ID=?, NAME=?, DATA=?");
    PreparedStatement prep2 = conn.prepareStatement("INSERT INTO TEST3 VALUES(?, ?, ?)");
    checkParameter(prep1, 1, "java.lang.Integer", 4, "INTEGER", 10, 0);
    checkParameter(prep1, 2, "java.lang.String", 12, "VARCHAR", 255, 0);
    checkParameter(prep1, 3, "java.math.BigDecimal", 3, "DECIMAL", 10, 2);
    checkParameter(prep2, 1, "java.lang.Integer", 4, "INTEGER", 10, 0);
    checkParameter(prep2, 2, "java.lang.String", 12, "VARCHAR", 255, 0);
    checkParameter(prep2, 3, "java.math.BigDecimal", 3, "DECIMAL", 10, 2);
    PreparedStatement prep3 = conn
            .prepareStatement("SELECT * FROM TEST3 WHERE ID=? AND NAME LIKE ? AND ?>DATA");
    checkParameter(prep3, 1, "java.lang.Integer", 4, "INTEGER", 10, 0);
    checkParameter(prep3, 2, "java.lang.String", 12, "VARCHAR", 0, 0);
    checkParameter(prep3, 3, "java.math.BigDecimal", 3, "DECIMAL", 10, 2);
    stat.execute("DROP TABLE TEST3");
}

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