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Diffstat (limited to 'storage/ndb/include/ndbapi/NdbRecAttr.hpp')
| -rw-r--r-- | storage/ndb/include/ndbapi/NdbRecAttr.hpp | 416 |
1 files changed, 416 insertions, 0 deletions
diff --git a/storage/ndb/include/ndbapi/NdbRecAttr.hpp b/storage/ndb/include/ndbapi/NdbRecAttr.hpp new file mode 100644 index 00000000000..5d9b0832e18 --- /dev/null +++ b/storage/ndb/include/ndbapi/NdbRecAttr.hpp @@ -0,0 +1,416 @@ +/* Copyright (C) 2003 MySQL AB + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ + +#ifndef NdbRecAttr_H +#define NdbRecAttr_H + +#include "NdbDictionary.hpp" +#include "Ndb.hpp" + +class NdbOperation; + +/** + * @class NdbRecAttr + * @brief Contains value of an attribute. + * + * NdbRecAttr objects are used to store the attribute value + * after retrieving the value from the NDB Cluster using the method + * NdbOperation::getValue. The objects are allocated by the NDB API. + * An example application program follows: + * + * @code + * MyRecAttr = MyOperation->getValue("ATTR2", NULL); + * if (MyRecAttr == NULL) goto error; + * + * if (MyTransaction->execute(Commit) == -1) goto error; + * + * ndbout << MyRecAttr->u_32_value(); + * @endcode + * For more examples, see + * @ref ndbapi_simple.cpp. + * + * @note The NdbRecAttr object is instantiated with its value when + * NdbTransaction::execute is called. Before this, the value is + * undefined. (NdbRecAttr::isNULL can be used to check + * if the value is defined or not.) + * This means that an NdbRecAttr object only has valid information + * between the time of calling NdbTransaction::execute and + * the time of Ndb::closeTransaction. + * The value of the null indicator is -1 until the + * NdbTransaction::execute method have been called. + * + * For simple types, there are methods which directly getting the value + * from the NdbRecAttr object. + * + * To get a reference to the value, there are two methods: + * NdbRecAttr::aRef (memory is released by NDB API) and + * NdbRecAttr::getAttributeObject (memory must be released + * by application program). + * The two methods may return different pointers. + * + * There are also methods to check attribute type, attribute size and + * array size. + * The method NdbRecAttr::arraySize returns the number of elements in the + * array (where each element is of size given by NdbRecAttr::attrSize). + * The NdbRecAttr::arraySize method is needed when reading variable-sized + * attributes. + * + * @note Variable-sized attributes are not yet supported. + */ +class NdbRecAttr +{ +#ifndef DOXYGEN_SHOULD_SKIP_INTERNAL + friend class NdbOperation; + friend class NdbIndexScanOperation; + friend class NdbEventOperationImpl; + friend class NdbReceiver; + friend class Ndb; + friend class NdbOut& operator<<(class NdbOut&, const class AttributeS&); +#endif + +public: + /** + * @name Getting meta information + * @{ + */ + const NdbDictionary::Column * getColumn() const; + + /** + * Get type of column + * @return Data type of the column + */ + NdbDictionary::Column::Type getType() const; + + /** + * Get attribute (element) size in bytes. + * + */ + Uint32 get_size_in_bytes() const { return m_size_in_bytes; } + + /** @} *********************************************************************/ + /** + * @name Getting stored value + * @{ + */ + + /** + * Check if attribute value is NULL. + * + * @return -1 = Not defined (Failure or + * NdbTransaction::execute not yet called).<br> + * 0 = Attribute value is defined, but not equal to NULL.<br> + * 1 = Attribute value is defined and equal to NULL. + */ + int isNULL() const; + + /** + * Get value stored in NdbRecAttr object. + * + * @return 64 bit long value. + */ + Int64 int64_value() const; + + /** + * Get value stored in NdbRecAttr object. + * + * @return 32 bit int value. + */ + Int32 int32_value() const; + + /** + * Get value stored in NdbRecAttr object. + * + * @return Short value. + */ + short short_value() const; + + /** + * Get value stored in NdbRecAttr object. + * + * @return Char value. + */ + char char_value() const; + + /** + * Get value stored in NdbRecAttr object. + * + * @return 64 bit unsigned value. + */ + Uint64 u_64_value() const; + + /** + * Get value stored in NdbRecAttr object. + * + * @return 32 bit unsigned value. + */ + Uint32 u_32_value() const; + + /** + * Get value stored in NdbRecAttr object. + * + * @return Unsigned short value. + */ + Uint16 u_short_value() const; + + /** + * Get value stored in NdbRecAttr object. + * + * @return Unsigned char value. + */ + Uint8 u_char_value() const; + + /** + * Get value stored in NdbRecAttr object. + * + * @return Float value. + */ + float float_value() const; + + /** + * Get value stored in NdbRecAttr object. + * + * @return Double value. + */ + double double_value() const; + + /** @} *********************************************************************/ + /** + * @name Getting reference to stored value + * @{ + */ + + /** + * Get reference to attribute value. + * + * Returns a char*-pointer to the value. + * The pointer is aligned appropriately for the data type. + * The memory is released when Ndb::closeTransaction is executed + * for the transaction which read the value. + * + * @note The memory is released by NDB API. + * + * @note The pointer to the attribute value stored in an NdbRecAttr + * object (i.e. the pointer returned by aRef) is constant. + * This means that this method can be called anytime after + * NdbOperation::getValue has been called. + * + * @return Pointer to attribute value. + */ + char* aRef() const; + + /** @} *********************************************************************/ + + /** + * Make a copy of RecAttr object including all data. + * + * @note Copy needs to be deleted by application program. + */ + NdbRecAttr * clone() const; + + /** + * Destructor + * + * @note You should only delete RecAttr-copies, + * i.e. objects that has been cloned. + */ + ~NdbRecAttr(); + +public: +#ifndef DOXYGEN_SHOULD_SKIP_INTERNAL + const NdbRecAttr* next() const; +#endif +private: + + Uint32 attrId() const; /* Get attribute id */ + bool setNULL(); /* Set NULL indicator */ + void setUNDEFINED(); // + + bool receive_data(const Uint32*, Uint32); + + void release(); /* Release memory if allocated */ + void init(); /* Initialise object when allocated */ + + NdbRecAttr(Ndb*); + void next(NdbRecAttr* aRecAttr); + NdbRecAttr* next(); + + int setup(const class NdbDictionary::Column* col, char* aValue); + int setup(const class NdbColumnImpl* anAttrInfo, char* aValue); + /* Set up attributes and buffers */ + bool copyoutRequired() const; /* Need to copy data to application */ + void copyout(); /* Copy from storage to application */ + + Uint64 theStorage[4]; /* The data storage here if <= 32 bytes */ + Uint64* theStorageX; /* The data storage here if > 32 bytes */ + char* theValue; /* The data storage in the application */ + void* theRef; /* Pointer to one of above */ + + NdbRecAttr* theNext; /* Next pointer */ + Uint32 theAttrId; /* The attribute id */ + + Int32 m_size_in_bytes; + const NdbDictionary::Column* m_column; + + friend struct Ndb_free_list_t<NdbRecAttr>; +}; + +#ifndef DOXYGEN_SHOULD_SKIP_INTERNAL + +inline +NdbDictionary::Column::Type +NdbRecAttr::getType() const { + return m_column->getType(); +} + +inline +const NdbDictionary::Column * +NdbRecAttr::getColumn() const { + return m_column; +} + +inline +Int32 +NdbRecAttr::int32_value() const +{ + return *(Int32*)theRef; +} + +inline +short +NdbRecAttr::short_value() const +{ + return *(short*)theRef; +} + +inline +char +NdbRecAttr::char_value() const +{ + return *(char*)theRef; +} + +inline +Uint32 +NdbRecAttr::u_32_value() const +{ + return *(Uint32*)theRef; +} + +inline +Uint16 +NdbRecAttr::u_short_value() const +{ + return *(Uint16*)theRef; +} + +inline +Uint8 +NdbRecAttr::u_char_value() const +{ + return *(Uint8*)theRef; +} + +inline +void +NdbRecAttr::release() +{ + if (theStorageX != 0) { + delete [] theStorageX; + theStorageX = 0; + } +} + +inline +void +NdbRecAttr::init() +{ + theStorageX = 0; + theValue = 0; + theRef = 0; + theNext = 0; + theAttrId = 0xFFFF; +} + +inline +void +NdbRecAttr::next(NdbRecAttr* aRecAttr) +{ + theNext = aRecAttr; +} + +inline +NdbRecAttr* +NdbRecAttr::next() +{ + return theNext; +} + +inline +const NdbRecAttr* +NdbRecAttr::next() const +{ + return theNext; +} + +inline +char* +NdbRecAttr::aRef() const +{ + return (char*)theRef; +} + +inline +bool +NdbRecAttr::copyoutRequired() const +{ + return theRef != theValue && theValue != 0; +} + +inline +Uint32 +NdbRecAttr::attrId() const +{ + return theAttrId; +} + +inline +bool +NdbRecAttr::setNULL() +{ + m_size_in_bytes= 0; + return true; +} + +inline +int +NdbRecAttr::isNULL() const +{ + return m_size_in_bytes == 0 ? 1 : (m_size_in_bytes > 0 ? 0 : -1); +} + +inline +void +NdbRecAttr::setUNDEFINED() +{ + m_size_in_bytes= -1; +} + +class NdbOut& operator <<(class NdbOut&, const NdbRecAttr &); + +#endif // ifndef DOXYGEN_SHOULD_SKIP_INTERNAL + +#endif + |