我的问题是：在使用ORA-01704: string literal too long s插入（或在查询中执行任何操作）时，如何解决CLOB错误？
我希望得到这样的查询：
INSERT ALL
INTO mytable VALUES ('clob1')
INTO mytable VALUES ('clob2') --some of these clobs are more than 4000 characters...
INTO mytable VALUES ('clob3')
SELECT * FROM dual;
当我尝试使用实际值时，虽然我得到了ORA-01704: string literal too long。这很明显，但是如何插入clobs（或者使用clob执行任何语句）？
我试过看question，但我认为它没有我想要的东西。我拥有的clob在List<String>中，我会遍历它们来制作声明。我的代码如下：
private void insertQueries(String tempTableName) throws FileNotFoundException, DataException, SQLException, IOException {
String preQuery = " into " + tempTableName + " values ('";
String postQuery = "')" + StringHelper.newline;
StringBuilder inserts = new StringBuilder("insert all" + StringHelper.newline);
List<String> readQueries = getDomoQueries();
for (String query : readQueries) {
inserts.append(preQuery).append(query).append(postQuery);
}
inserts.append("select * from dual;");
DatabaseController.getInstance().executeQuery(databaseConnectionURL, inserts.toString());
}
public ResultSet executeQuery(String connection, String query) throws DataException, SQLException {
Connection conn = ConnectionPool.getInstance().get(connection);
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery(query);
conn.commit();
ConnectionPool.getInstance().release(conn);
return rs;
}
答案 0 :(得分：7)
你正在变得复杂。
为列表中的每个clob使用PreparedStatement和addBatch（）：
String sql = "insert into " + tempTableName + " values (?)";
PreparedStatement stmt = connection.prepareStatement(sql);
for (String query : readQueries) {
stmt.setCharacterStream(1, new StringReader(query), query.lenght());
stmt.addBatch();
}
stmt.exececuteBatch();
不要乱转字符串，文字长度没问题，不需要创建临时clobs。而且大多数可能与使用单个INSERT ALL语句一样快。
如果您使用的是当前驱动程序（> 10.2），那么我认为setCharacterStream（）调用和Reader的创建也不是必需的。一个简单的setString(1, query)很可能也会起作用。
答案 1 :(得分：2)
您需要使用绑定变量，而不是使用字符串连接来构建SQL语句。从安全性，性能和健壮性的角度来看，这将是有益的，因为它将降低SQL注入攻击的风险，减少Oracle花费在SQL语句上进行硬解析所花费的时间，并将消除那里的潜力是字符串中的一个特殊字符，它导致生成无效的SQL语句（即单引号）。
我希望你想要像
这样的东西private void insertQueries(String tempTableName) throws FileNotFoundException, DataException, SQLException, IOException {
String preQuery = " into " + tempTableName + " values (?)" + StringHelper.newline;
StringBuilder inserts = new StringBuilder("insert all" + StringHelper.newline);
List<String> readQueries = getDomoQueries();
for (String query : readQueries) {
inserts.append(preQuery);
}
inserts.append("select * from dual");
Connection conn = ConnectionPool.getInstance().get(connection);
PreparedStatement pstmt = conn.prepareStatement(
inserts);
int i = 1;
for (String query : readQueries) {
Clob clob = CLOB.createTemporary(conn, false, oracle.sql.CLOB.DURATION_SESSION);
clob.setString(i, query);
pstmt.setClob(i, clob);
i = i + 1;
}
pstmt.executeUpdate();
}
答案 2 :(得分：2)
BLOB（二进制大对象）和CLOB（字符大对象）是特殊的数据类型，可以以对象或文本的形式保存大块数据。 Blob和Clob对象将对象的数据作为流保存到数据库中。
一段代码示例：
public class TestDB {
public static void main(String[] args) {
try {
/** Loading the driver */
Class.forName("com.oracle.jdbc.Driver");
/** Getting Connection */
Connection con = DriverManager.getConnection("Driver URL","test","test");
PreparedStatement pstmt = con.prepareStatement("insert into Emp(id,name,description)values(?,?,?)");
pstmt.setInt(1,5);
pstmt.setString(2,"Das");
// Create a big CLOB value...AND inserting as a CLOB
StringBuffer sb = new StringBuffer(400000);
sb.append("This is the Example of CLOB ..");
String clobValue = sb.toString();
pstmt.setString(3, clobValue);
int i = pstmt.executeUpdate();
System.out.println("Done Inserted");
pstmt.close();
con.close();
// Retrive CLOB values
Connection con = DriverManager.getConnection("Driver URL","test","test");
PreparedStatement pstmt = con.prepareStatement("select * from Emp where id=5");
ResultSet rs = pstmt.executeQuery();
Reader instream = null;
int chunkSize;
if (rs.next()) {
String name = rs.getString("name");
java.sql.Clob clob = result.getClob("description")
StringBuffer sb1 = new StringBuffer();
chunkSize = ((oracle.sql.CLOB)clob).getChunkSize();
instream = clob.getCharacterStream();
BufferedReader in = new BufferedReader(instream);
String line = null;
while ((line = in.readLine()) != null) {
sb1.append(line);
}
if (in != null) {
in.close();
}
// this is the clob data converted into string
String clobdata = sb1.toString();
}
} catch (Exception e) {
e.printStackTrace();
}
}
}
答案 3 :(得分：2)
您必须牢记以下自动切换大数据的输入模式。 有三种输入模式，如下所示：直接绑定，流绑定和LOB绑定。
对于PL / SQL语句
setBytes和setBinary流方法对小于32767字节的数据使用直接绑定。
setBytes和setBinaryStream方法对大于32766字节的数据使用LOB绑定。
setString，setCharacterStream和setAsciiStream方法对数据库字符集中小于32767字节的数据使用直接绑定。
setString，setCharacterStream和setAsciiStream方法对数据库字符集中大于32766字节的数据使用LOB绑定。
oracle.jdbc.OraclePreparedStatement接口中的setBytesForBlob和setStringForClob方法对任何数据大小都使用LOB绑定。
以下是将文件内容放入PLSQL过程的输入CLOB参数的示例：
public int fileToClob( FileItem uploadFileItem ) throws SQLException, IOException
{
//for using stmt.setStringForClob method, turn the file to a big String
FileItem item = uploadFileItem;
InputStream inputStream = item.getInputStream();
InputStreamReader inputStreamReader = new InputStreamReader( inputStream );
BufferedReader bufferedReader = new BufferedReader( inputStreamReader );
StringBuffer stringBuffer = new StringBuffer();
String line = null;
while((line = bufferedReader.readLine()) != null) { //Read till end
stringBuffer.append(line);
stringBuffer.append("\n");
}
String fileString = stringBuffer.toString();
bufferedReader.close();
inputStreamReader.close();
inputStream.close();
item.delete();
OracleCallableStatement stmt;
String strFunction = "{ call p_file_to_clob( p_in_clob => ? )}";
stmt= (OracleCallableStatement)conn.prepareCall(strFunction);
try{
SasUtility servletUtility = sas.SasUtility.getInstance();
stmt.setStringForClob(1, fileString );
stmt.execute();
} finally {
stmt.close();
}
}
答案 4 :(得分：0)
我，我喜欢使用java.sql。*包中的类，而不是oracle。*的东西。对我来说，简单的方法
Connection con = ...;
try (PreparedStatement pst = con.prepareStatement(
"insert into tbl (other_fld, clob_fld) values (?,?)", new String[]{"tbl_id"});
) {
Clob clob = con.createClob();
readIntoClob(clob, inputStream);
pst.setString(1, "other");
pst.setClob(2, clob);
pst.executeUpdate();
try (ResultSet rst = pst.getGeneratedKeys()) {
if (rst == null || !rst.next()) {
throw new Exception("error with getting auto-generated key");
}
id = rst.getBigDecimal(1);
}
停止工作。 con.createClob（）由于该版本中未知的原因而返回null，所以我不得不重复两次（花了我很长时间才弄清楚，所以我在这里分享...）
try (PreparedStatement pst = con.prepareStatement(
"insert into tbl (other_fld) values (?)", new String[]{"tbl_id"});
PreparedStatement getClob= con.prepareStatement(
"select clob_fld from tbl where tbl_id = ? for update");
) {
Clob clob = con.createClob();
readIntoClob(clob, inputStream);
pst.setString(1, "other");
pst.executeUpdate();
try (ResultSet rst = pst.getGeneratedKeys()) {
if (rst == null || !rst.next()) {
throw new Exception("error with getting auto-generated key");
}
id = rst.getBigDecimal(1);
}
// fetch back fresh record, with the Clob
getClob.setBigDecimal(1, id);
getClob.execute();
try (ResultSet rst = getClob.getResultSet()) {
if (rst == null || !rst.next()) {
throw new Exception("error with fetching back clob");
}
Clob c = rst.getClob(1);
// Fill in data
readIntoClob(c, stream);
// that's all
}
} catch (SQLException) {
...
}
为了完整性，这里是
// Read data from an input stream and insert it in to the clob column
private static void readIntoClob(Clob clob, InputStream stream) {
try (BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(stream))) {
char[] buffer = new char[CHUNK_BUFFER_SIZE];
int charsRead;
try (Writer wr = clob.setCharacterStream(1L)) {
// Loop for reading of chunk of data and then write into the clob.
while ((charsRead = bufferedReader.read(buffer)) != -1) {
wr.write(buffer, 0, charsRead);
}
} catch (SQLException | IOException ex) {
...
}
}
}
这是SO上其他地方的内容，
答案 5 :(得分：0)
在github上查看一些与CLOB相关的示例。