dbSendQuery-methods(ROracle)
dbSendQuery-methods()所属R语言包：ROracle
Execute a statement on a given database connection
在一个给定的数据库连接，执行语句
译者：生物统计家园网 机器人LoveR
描述----------Description----------
These methods are straight-forward implementations of the corresponding generic functions except for the execute method which is an ROracle specific DBI extension.
这些方法是直接的相应的通用功能的实现，除了execute方法这是一个ROracle的特定DBI扩展。
参数----------Arguments----------
参数：conn
an OraConnection object.
OraConnection对象。
参数：statement
a character vector of length 1 with the SQL statement.
字符向量长度为1的SQL语句。
参数：res
an OraResult object.
OraResult对象。
参数：data
a data.frame specifying bind data
数据框指定的数据绑定
参数：prefetch
a logical value indicating TRUE or FALSE. When set to TRUE, ROracle will use OCI prefetch buffers to retrieve additional data from the server thus saving memory required in RODBI/ROOCI by allocating a single row buffer to fetch the data from OCI. Using prefetch results in a fetch call for every row. By default, prefetch is FALSE and array fetch is used to retrive the data from server.
一个TRUE或FALSE的逻辑值，该值指示。当设置为TRUE，ROracle的将使用OCI预取的缓冲区，以获取额外的数据从服务器，从而节省内存需要分配一个行缓冲区中获取数据OCI在RODBI / ROOCI。在提取使用预取结果的每一行调用。默认情况下，预取FALSE和数组提取使用，以检索数据从服务器。
参数：bulk_read
an integer value indicating the number of rows to fetch at a time. Default is 25L. When prefetch option is select, memory is allocated for prefetch buffers and OCI will fetch those many rows at a time. When prefetch is not used(default) memory is allocated in RODBI/ROOCI define buffers. Setting this to a large value will result in more memory allocated based on the number of columns in the select list and the types of columns. For a column of character, define buffers are allocated using the maximum width times the NLS maximum width. Application should adjust this value based on the query result and a larger value will benefit queries that return a large result. Application can tune this value to its need.
一个整数值，表示一次获取的行数。默认为25L。当预取选项选择，内存分配预取缓冲器和保监处会取那些行一次。如果不使用预取（默认）内存是分配在RODBI / ROOCI定义缓冲区。其设置一个较大的值，将导致更多的内存分配的基础上选择列表中的列的数量和类型的列。对于列的字符，定义缓冲区分配使用的最大宽度免入息审查贷款计划的最大宽度。应用程序应该调整这个值根据查询结果和更大的值将受益查询返回的结果。应用程序可以调整此值，其需要。
参数：lob_prefetch
an integer value indicating the size of lob data that can be prefetched and cached while fetching lob data. Default is 1024L.
一个整数值，表示LOB数据的大小，可以获取LOB数据预取和缓存，而。默认为1024L。
参数：...
additional parameters.
附加参数。
Details
详细信息----------Details----------
implementation does execute query statement and fetch result data from database.
实现不执行查询语句，从数据库中获取结果数据。
implementation does execute query statement and return result set to the application. Now application can perform operations on result set.
实现不执行查询语句并返回结果集的应用程序。现在，应用程序可以执行的操作结果集。
implementation does free resources occupied by result set.
实现执行结果集所占用的免费资源。
implementation does retrieve error information.
实施检索错误信息。
implementation does execute query statement.
实现不执行查询语句。
值----------Value----------
参数：dbSendQuery
an object OraResult whose class extends DBIResult. This object is used to fetch data from database, using the function fetch.
对象OraResult的类扩展DBIResult。该对象用于从数据库中提取数据，使用功能fetch。
副作用----------Side Effects----------
query statement is executed and data has fetched from database.
执行查询语句和数据从数据库中取出。
query statement is executed, but note that data needs to fetch through calls to fetch.
执行查询语句，但是请注意，需要获取数据通过调用fetch。
resources acquired by result set has free.
资源获得的结果集。
error information retrieved and then cleaned from driver.
错误信息检索，然后从驱动器清洗。
query statement is executed.
执行查询语句。
参考文献----------References----------
http://www.oracle.com/technetwork/indexes/documentation/index.html.
参见----------See Also----------
Oracle, dbDriver, dbConnect, fetch, dbCommit, dbGetInfo, dbReadTable.
Oracle，dbDriver，dbConnect，fetch，dbCommit，dbGetInfo，dbReadTable。
实例----------Examples----------
## Not run: [＃不运行：]
drv <- dbDriver("Oracle")
con <- dbConnect(drv, "scott", "tiger")
res <- dbSendQuery(con, "select * from emp where deptno = :1",
data = data.frame(deptno = 10))
data <- fetch(res, n = -1)
res2 <- dbSendQuery(con, "select * from emp where deptno = :1",
data1 = data.frame(deptno = 10), prefetch=TRUE,
bulk_read=2L)
data1 <- fetch(res2, n = -1)
res3 <- dbSendQuery(con, "select * from emp where deptno = :1",
data2 = data.frame(deptno = 10), bulk_read=10L)
data2 <- fetch(res3, n = -1)
res4 <- dbSendQuery(con, "select * from emp where ename = :1",
data3 = data.frame(ename = 'SMITH'),
lob_prefetch=3000L)
data3 <- fetch(res4, n = -1)
## End(Not run)[＃（不执行）]
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注：
注1：为了方便大家学习，本文档为生物统计家园网机器人LoveR翻译而成，仅供个人R语言学习参考使用，生物统计家园保留版权。
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发表于 2012-9-27 23:26:22
