本文整理汇总了C++中DatabaseConnection::existsTable方法的典型用法代码示例。如果您正苦于以下问题：C++ DatabaseConnection::existsTable方法的具体用法？C++ DatabaseConnection::existsTable怎么用？C++ DatabaseConnection::existsTable使用的例子？那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在类DatabaseConnection的用法示例。
在下文中一共展示了DatabaseConnection::existsTable方法的2个代码示例，这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞，您的评价将有助于系统推荐出更棒的C++代码示例。
示例1: dbExistsTable
SEXP dbExistsTable(SEXP dbi_conn_sexp, SEXP tableName_sexp) {
SEXP ans;
if(TYPEOF(dbi_conn_sexp) != EXTPTRSXP || dbi_conn_sexp == R_NilValue) {
return R_NilValue;
}
DatabaseConnection* conn = reinterpret_cast<DatabaseConnection*>(R_ExternalPtrAddr(dbi_conn_sexp));
if(!conn) {
// throw bad_connection_object
REprintf("bad database connection.\n");
return R_NilValue;
}
const char* tableName = CHAR(STRING_ELT(tableName_sexp,0));
PROTECT(ans = allocVector(LGLSXP,1));
LOGICAL(ans)[0] = static_cast<int>(conn->existsTable(tableName));
UNPROTECT(1);
return ans;
}示例2: dbWriteTable
// return number of rows written to database
// using both overwrite and append is a bad design decision
// there should just be overwrite, which will drop the table if it exists
// append should be automatic if the table exists, and should fail if the row formats don't match up
// having both overwrite and append just complicates the logic of this function
SEXP dbWriteTable(SEXP dbi_conn_sexp, SEXP tableName_sexp, SEXP value_sexp, SEXP writeRowNames_sexp, SEXP overWrite_sexp, SEXP append_sexp) {
SEXP ans;
int rows;
if(TYPEOF(dbi_conn_sexp) != EXTPTRSXP || dbi_conn_sexp == R_NilValue) {
return R_NilValue;
}
DatabaseConnection* conn = reinterpret_cast<DatabaseConnection*>(R_ExternalPtrAddr(dbi_conn_sexp));
if(!conn) {
// throw bad_connection_object
REprintf("bad database connection.\n");
return ScalarInteger(0);
}
if(TYPEOF(tableName_sexp) != STRSXP) {
REprintf("ERROR: tableName is not a string.\n");
return ScalarInteger(0);
}
const char* tableName = CHAR(STRING_ELT(tableName_sexp,0));
const bool writeRowNames = static_cast<bool>(LOGICAL(writeRowNames_sexp)[0]);
const bool overWrite = static_cast<bool>(LOGICAL(overWrite_sexp)[0]);
if(conn->existsTable(tableName) && overWrite) {
if(!conn->removeTable(tableName)) {
REprintf("could not remove existing table (aborting).\n");
return ScalarInteger(0);
}
}
try {
rows = conn->writeTable(tableName, value_sexp, writeRowNames);
} catch (MapToTypeNotImplemented& e) {
REprintf("%s\n",e.what());
return R_NilValue;
}
PROTECT(ans = allocVector(INTSXP,1));
INTEGER(ans)[0] = rows;
UNPROTECT(1);
return ans;
}