在 postgresql-jdbc 中使用二进制传输时，我在使用返回文本数组类型的准备好的语句时遇到问题：它返回null应该具有值的位置。事实上，在我的测试中，它仅从循环中的第 6 次迭代开始发生。
如果我将binaryTransfer属性设置为false，它工作正常。
我已经在 PG 9.2 和 9.3 数据库中使用 postgresql-9.3-1102.jdbc4.jar 对其进行了测试。
对于不实现二进制传输的较旧的 jdbc 版本（即 postgresql-9.0-801.jdbc4.jar），它可以正常工作。
这是我测试的代码：
import java.sql.Connection;
import java.sql.Driver;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.Properties;
public class TestMe {
public static void main(String[] args) throws SQLException {
String url = "jdbc:postgresql://localhost:5433/pi1";
Connection conn = null;
// org.postgresql.Driver.setLogLevel(org.postgresql.Driver.DEBUG);
Properties connectionProps = new Properties();
connectionProps.put("user", "tad");
connectionProps.put("password", "password");
connectionProps.put("binaryTransfer", "true");
conn = DriverManager.getConnection(url, connectionProps);
Driver driver = DriverManager.getDriver(url);
conn = driver.connect(url, connectionProps);
System.out.println(org.postgresql.Driver.MAJORVERSION + "."
+ org.postgresql.Driver.MINORVERSION);
PreparedStatement fs = conn
.prepareStatement("SELECT proargnames FROM pg_proc where proname ='pg_cursor'");
for (int i = 0; i < 7; i++) {
ResultSet rs = fs.executeQuery();
rs.next();
System.out.println(rs.getArray(1));
rs.close();
}
}
}
这是输出
9.3
{name,statement,is_holdable,is_binary,is_scrollable,creation_time}
{name,statement,is_holdable,is_binary,is_scrollable,creation_time}
{name,statement,is_holdable,is_binary,is_scrollable,creation_time}
{name,statement,is_holdable,is_binary,is_scrollable,creation_time}
{name,statement,is_holdable,is_binary,is_scrollable,creation_time}
null
null
这是相同的输出设置 DEBUG 日志级别：
13:18:59.474 (1) PostgreSQL 9.3 JDBC4 (build 1102)
13:18:59.485 (1) Trying to establish a protocol version 3 connection to localhost:5433
13:18:59.519 (1) Receive Buffer Size is 131003
13:18:59.519 (1) Send Buffer Size is 331875
13:18:59.519 (1) FE=> StartupPacket(user=tad, database=pi1, client_encoding=UTF8, DateStyle=ISO, extra_float_digits=2, TimeZone=Europe/Madrid)
13:18:59.522 (1) <=BE AuthenticationOk
13:18:59.533 (1) <=BE ParameterStatus(application_name = )
13:18:59.533 (1) <=BE ParameterStatus(client_encoding = UTF8)
13:18:59.534 (1) <=BE ParameterStatus(DateStyle = ISO, DMY)
13:18:59.534 (1) <=BE ParameterStatus(integer_datetimes = on)
13:18:59.534 (1) <=BE ParameterStatus(IntervalStyle = postgres)
13:18:59.534 (1) <=BE ParameterStatus(is_superuser = on)
13:18:59.534 (1) <=BE ParameterStatus(server_encoding = UTF8)
13:18:59.534 (1) <=BE ParameterStatus(server_version = 9.3.5)
13:18:59.534 (1) <=BE ParameterStatus(session_authorization = tad)
13:18:59.534 (1) <=BE ParameterStatus(standard_conforming_strings = on)
13:18:59.534 (1) <=BE ParameterStatus(TimeZone = Europe/Madrid)
13:18:59.534 (1) <=BE BackendKeyData(pid=25866,ckey=1929735537)
13:18:59.534 (1) <=BE ReadyForQuery(I)
13:18:59.536 (1) simple execute, handler=org.postgresql.core.SetupQueryRunner$SimpleResultHandler@81f59f1, maxRows=0, fetchSize=0, flags=23
13:18:59.537 (1) FE=> Parse(stmt=null,query="SET extra_float_digits = 3",oids={})
13:18:59.538 (1) FE=> Bind(stmt=null,portal=null)
13:18:59.538 (1) FE=> Execute(portal=null,limit=1)
13:18:59.538 (1) FE=> Sync
13:18:59.539 (1) <=BE ParseComplete [null]
13:18:59.539 (1) <=BE BindComplete [null]
13:18:59.539 (1) <=BE CommandStatus(SET)
13:18:59.539 (1) <=BE ReadyForQuery(I)
13:18:59.540 (1) compatible = 9.3
13:18:59.540 (1) loglevel = 2
13:18:59.540 (1) prepare threshold = 5
13:18:59.544 (1) types using binary send = INT8_ARRAY,TIMESTAMPTZ,FLOAT4_ARRAY,FLOAT8_ARRAY,UUID,TEXT_ARRAY,VARCHAR_ARRAY,BYTEA,TIME,FLOAT4,FLOAT8,INT2_ARRAY,TIMETZ,INT2,INT8,INT4,INT4_ARRAY,TIMESTAMP,POINT,BOX
13:18:59.546 (1) types using binary receive = INT8_ARRAY,TIMESTAMPTZ,FLOAT4_ARRAY,FLOAT8_ARRAY,UUID,TEXT_ARRAY,VARCHAR_ARRAY,BYTEA,TIME,DATE,FLOAT4,FLOAT8,INT2_ARRAY,TIMETZ,INT2,INT8,INT4,INT4_ARRAY,TIMESTAMP,POINT,BOX
13:18:59.546 (1) integer date/time = true
getConnection returning org.postgresql.Driver
DriverManager.getDriver("jdbc:postgresql://localhost:5433/pi1")
getDriver returning org.postgresql.Driver
13:18:59.556 (driver) Connecting with URL: jdbc:postgresql://localhost:5433/pi1
13:18:59.556 (2) PostgreSQL 9.3 JDBC4 (build 1102)
13:18:59.556 (2) Trying to establish a protocol version 3 connection to localhost:5433
13:18:59.557 (2) Receive Buffer Size is 131003
13:18:59.557 (2) Send Buffer Size is 331875
13:18:59.557 (2) FE=> StartupPacket(user=tad, database=pi1, client_encoding=UTF8, DateStyle=ISO, extra_float_digits=2, TimeZone=Europe/Madrid)
13:18:59.560 (2) <=BE AuthenticationOk
13:18:59.560 (2) <=BE ParameterStatus(application_name = )
13:18:59.560 (2) <=BE ParameterStatus(client_encoding = UTF8)
13:18:59.560 (2) <=BE ParameterStatus(DateStyle = ISO, DMY)
13:18:59.561 (2) <=BE ParameterStatus(integer_datetimes = on)
13:18:59.561 (2) <=BE ParameterStatus(IntervalStyle = postgres)
13:18:59.561 (2) <=BE ParameterStatus(is_superuser = on)
13:18:59.561 (2) <=BE ParameterStatus(server_encoding = UTF8)
13:18:59.561 (2) <=BE ParameterStatus(server_version = 9.3.5)
13:18:59.561 (2) <=BE ParameterStatus(session_authorization = tad)
13:18:59.561 (2) <=BE ParameterStatus(standard_conforming_strings = on)
13:18:59.561 (2) <=BE ParameterStatus(TimeZone = Europe/Madrid)
13:18:59.561 (2) <=BE BackendKeyData(pid=25867,ckey=1041579294)
13:18:59.561 (2) <=BE ReadyForQuery(I)
13:18:59.561 (2) simple execute, handler=org.postgresql.core.SetupQueryRunner$SimpleResultHandler@68a48d59, maxRows=0, fetchSize=0, flags=23
13:18:59.561 (2) FE=> Parse(stmt=null,query="SET extra_float_digits = 3",oids={})
13:18:59.562 (2) FE=> Bind(stmt=null,portal=null)
13:18:59.562 (2) FE=> Execute(portal=null,limit=1)
13:18:59.562 (2) FE=> Sync
13:18:59.562 (2) <=BE ParseComplete [null]
13:18:59.562 (2) <=BE BindComplete [null]
13:18:59.563 (2) <=BE CommandStatus(SET)
13:18:59.563 (2) <=BE ReadyForQuery(I)
13:18:59.563 (2) compatible = 9.3
13:18:59.563 (2) loglevel = 2
13:18:59.563 (2) prepare threshold = 5
13:18:59.564 (2) types using binary send = INT8_ARRAY,TIMESTAMPTZ,FLOAT4_ARRAY,FLOAT8_ARRAY,UUID,TEXT_ARRAY,VARCHAR_ARRAY,BYTEA,TIME,FLOAT4,FLOAT8,INT2_ARRAY,TIMETZ,INT2,INT8,INT4,INT4_ARRAY,TIMESTAMP,POINT,BOX
13:18:59.566 (2) types using binary receive = INT8_ARRAY,TIMESTAMPTZ,FLOAT4_ARRAY,FLOAT8_ARRAY,UUID,TEXT_ARRAY,VARCHAR_ARRAY,BYTEA,TIME,DATE,FLOAT4,FLOAT8,INT2_ARRAY,TIMETZ,INT2,INT8,INT4,INT4_ARRAY,TIMESTAMP,POINT,BOX
13:18:59.566 (2) integer date/time = true
9.3
13:18:59.580 (2) simple execute, handler=org.postgresql.jdbc2.AbstractJdbc2Statement$StatementResultHandler@2d6a5acd, maxRows=0, fetchSize=0, flags=17
13:18:59.580 (2) FE=> Parse(stmt=null,query="SELECT proargnames FROM pg_proc where proname ='pg_cursor'",oids={})
13:18:59.580 (2) FE=> Bind(stmt=null,portal=null)
13:18:59.581 (2) FE=> Describe(portal=null)
13:18:59.581 (2) FE=> Execute(portal=null,limit=0)
13:18:59.581 (2) FE=> Sync
13:18:59.582 (2) <=BE ParseComplete [null]
13:18:59.583 (2) <=BE BindComplete [null]
13:18:59.584 (2) <=BE RowDescription(1)
13:18:59.584 (2) Field(,TEXT_ARRAY,65535,T)
13:18:59.584 (2) <=BE DataRow(len=66)
13:18:59.585 (2) <=BE CommandStatus(SELECT 1)
13:18:59.602 (2) <=BE ReadyForQuery(I)
{name,statement,is_holdable,is_binary,is_scrollable,creation_time}
13:18:59.608 (2) simple execute, handler=org.postgresql.jdbc2.AbstractJdbc2Statement$StatementResultHandler@fc5d5e4, maxRows=0, fetchSize=0, flags=17
13:18:59.608 (2) FE=> Parse(stmt=null,query="SELECT proargnames FROM pg_proc where proname ='pg_cursor'",oids={})
13:18:59.608 (2) FE=> Bind(stmt=null,portal=null)
13:18:59.608 (2) FE=> Describe(portal=null)
13:18:59.608 (2) FE=> Execute(portal=null,limit=0)
13:18:59.608 (2) FE=> Sync
13:18:59.609 (2) <=BE ParseComplete [null]
13:18:59.609 (2) <=BE BindComplete [null]
13:18:59.609 (2) <=BE RowDescription(1)
13:18:59.610 (2) Field(,TEXT_ARRAY,65535,T)
13:18:59.610 (2) <=BE DataRow(len=66)
13:18:59.610 (2) <=BE CommandStatus(SELECT 1)
13:18:59.610 (2) <=BE ReadyForQuery(I)
{name,statement,is_holdable,is_binary,is_scrollable,creation_time}
13:18:59.610 (2) simple execute, handler=org.postgresql.jdbc2.AbstractJdbc2Statement$StatementResultHandler@55d73d3, maxRows=0, fetchSize=0, flags=17
13:18:59.611 (2) FE=> Parse(stmt=null,query="SELECT proargnames FROM pg_proc where proname ='pg_cursor'",oids={})
13:18:59.611 (2) FE=> Bind(stmt=null,portal=null)
13:18:59.611 (2) FE=> Describe(portal=null)
13:18:59.611 (2) FE=> Execute(portal=null,limit=0)
13:18:59.611 (2) FE=> Sync
13:18:59.612 (2) <=BE ParseComplete [null]
13:18:59.612 (2) <=BE BindComplete [null]
13:18:59.612 (2) <=BE RowDescription(1)
13:18:59.613 (2) Field(,TEXT_ARRAY,65535,T)
13:18:59.613 (2) <=BE DataRow(len=66)
13:18:59.613 (2) <=BE CommandStatus(SELECT 1)
13:18:59.613 (2) <=BE ReadyForQuery(I)
{name,statement,is_holdable,is_binary,is_scrollable,creation_time}
13:18:59.613 (2) simple execute, handler=org.postgresql.jdbc2.AbstractJdbc2Statement$StatementResultHandler@3a5f2465, maxRows=0, fetchSize=0, flags=17
13:18:59.614 (2) FE=> Parse(stmt=null,query="SELECT proargnames FROM pg_proc where proname ='pg_cursor'",oids={})
13:18:59.614 (2) FE=> Bind(stmt=null,portal=null)
13:18:59.614 (2) FE=> Describe(portal=null)
13:18:59.614 (2) FE=> Execute(portal=null,limit=0)
13:18:59.614 (2) FE=> Sync
13:18:59.615 (2) <=BE ParseComplete [null]
13:18:59.615 (2) <=BE BindComplete [null]
13:18:59.615 (2) <=BE RowDescription(1)
13:18:59.615 (2) Field(,TEXT_ARRAY,65535,T)
13:18:59.616 (2) <=BE DataRow(len=66)
13:18:59.616 (2) <=BE CommandStatus(SELECT 1)
13:18:59.616 (2) <=BE ReadyForQuery(I)
{name,statement,is_holdable,is_binary,is_scrollable,creation_time}
13:18:59.616 (2) simple execute, handler=org.postgresql.jdbc2.AbstractJdbc2Statement$StatementResultHandler@3c4e80d3, maxRows=0, fetchSize=0, flags=16
13:18:59.616 (2) FE=> Parse(stmt=S_1,query="SELECT proargnames FROM pg_proc where proname ='pg_cursor'",oids={})
13:18:59.616 (2) FE=> Bind(stmt=S_1,portal=null)
13:18:59.616 (2) FE=> Describe(portal=null)
13:18:59.617 (2) FE=> Execute(portal=null,limit=0)
13:18:59.617 (2) FE=> Sync
13:18:59.617 (2) <=BE ParseComplete [S_1]
13:18:59.618 (2) <=BE BindComplete [null]
13:18:59.618 (2) <=BE RowDescription(1)
13:18:59.618 (2) Field(,TEXT_ARRAY,65535,T)
13:18:59.618 (2) <=BE DataRow(len=66)
13:18:59.618 (2) <=BE CommandStatus(SELECT 1)
13:18:59.618 (2) <=BE ReadyForQuery(I)
{name,statement,is_holdable,is_binary,is_scrollable,creation_time}
13:18:59.618 (2) simple execute, handler=org.postgresql.jdbc2.AbstractJdbc2Statement$StatementResultHandler@7767d3c1, maxRows=0, fetchSize=0, flags=16
13:18:59.618 (2) FE=> Bind(stmt=S_1,portal=null)
13:18:59.618 (2) FE=> Execute(portal=null,limit=0)
13:18:59.619 (2) FE=> Sync
13:18:59.619 (2) <=BE BindComplete [null]
13:18:59.619 (2) <=BE DataRow(len=103)
13:18:59.619 (2) <=BE CommandStatus(SELECT 1)
13:18:59.619 (2) <=BE ReadyForQuery(I)
null
13:18:59.619 (2) simple execute, handler=org.postgresql.jdbc2.AbstractJdbc2Statement$StatementResultHandler@417f6125, maxRows=0, fetchSize=0, flags=16
13:18:59.620 (2) FE=> Bind(stmt=S_1,portal=null)
13:18:59.620 (2) FE=> Execute(portal=null,limit=0)
13:18:59.620 (2) FE=> Sync
13:18:59.620 (2) <=BE BindComplete [null]
13:18:59.620 (2) <=BE DataRow(len=103)
13:18:59.620 (2) <=BE CommandStatus(SELECT 1)
13:18:59.620 (2) <=BE ReadyForQuery(I)
null