The class qString encapsulates information for comparing string values. More...
#include <qExpr.h>
Public Member Functions | |
virtual qString * | dup () const |
virtual void | getTableNames (std::set< std::string > &plist) const |
Identify the data partitions involved in the query expression. | |
const char * | leftString () const |
virtual void | print (std::ostream &) const |
Print out the node in the string form. | |
virtual void | printFull (std::ostream &out) const |
Print out the full expression. | |
qString (const char *ls, const char *rs) | |
The constructor of qString. | |
const char * | rightString () const |
The class qString encapsulates information for comparing string values.
Only equality comparison is supported at this point. It does not ensure the names are valid in any way. When the check does happen, the left side will be checked first. If it matches the name of a ibis::column, the right side will be assumed to be the value one is trying to match. If the left side does not match any know column name, but the right side does, the right side will be assumed to name of column to be searched and the left side will be the value to search against. If neither matches the name of any column, the expression will evaluate to NULL (i.e., no hit).
ibis::qString::qString | ( | const char * | ls, |
const char * | rs | ||
) |
The constructor of qString.
The string rs must have matching quote if it is quoted. It may also contain meta character '\' that is used to escape the quote and other characters. The meta character will also be striped.
void ibis::qString::getTableNames | ( | std::set< std::string > & | plist | ) | const [virtual] |
Identify the data partitions involved in the query expression.
Return the list of data partition names in a set.
It records a '*' for the variables without explicit partition names.
Reimplemented from ibis::qExpr.
References ibis::qExpr::extractTableName().
void ibis::qString::print | ( | std::ostream & | out | ) | const [virtual] |
Print out the node in the string form.
The short-form of the print function.
It only prints information about the current node of the query expression tree.
Reimplemented from ibis::qExpr.
virtual void ibis::qString::printFull | ( | std::ostream & | out | ) | const [inline, virtual] |
Print out the full expression.
The long form of the print function.
It recursively prints out the whole query expression tree, which can be quite long.
Reimplemented from ibis::qExpr.
References ibis::qExpr::print().
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