Comparative Analysis of the Selected Relational Database Management Systems

Transcription

1 Comparative Analysis of the Selected Relational Database Management Systems R. Poljak, P. Poščić and D. Jakšić Department of informatics-university of Rijeka/ Rijeka, Croatia Abstract - The database management system is a software that enables easier work with databases i.e. to define database structure, retrieve stored data, enter data into the database and process the previously stored data in the database. In this article we have compared 3 relational database management systems () -, and. They are compared according to the simple criteria that we defined, such as the comparison of basic data, syntax, data types and speed performance. The main contribution of the article is a comparison of 3 different s by our own score criteria. I. INTRODUCTION Databases today are widely used in the field of information systems. Databases allow working with multiple levels of data, unlike conventional programming languages. They are made with the purpose to eliminate the weak points of automatic processing of data that have been most used during the 60s and 70s. Growing usage of databases has enabled the development of quality and reliable applications. The definition of a database according to [8] is a collection of interrelated data and stored in computers external memory. According to [8] system for database management is a server for a database, and with it you can create a database to display the required logical structure. It is also used to perform operations on data that its client tasks. In this paper we were working with database management systems that are based on the relational model. The relational model was designed by E. F. Codd in the 60s. The model uses mathematical concept of a relation and data and links between data are shown in table form. II. SPECIFICATIONS A. According to [1] is the most popular open source database in the world, because it has cost-effective delivery of data, with high-performance, stable e- commerce and online transaction processing. According to [1] is an integrated, safe for transactions, an ACID compliant database with full support for a return to the old data, the recovery after the destruction of the base and the possibility of row-level locking. provides ease of use, high performance, scalability, as well as packet drivers of the database and visual tools to help developers (database administration). database has the following characteristics: High performance and scalability - to satisfy the exponential growth of data loads and a number of users. Self-healing cluster replication - to improve the performance, stability and availability. Online modification of the scheme - in order to satisfy changing business requirements. B. According to [2] is an object-relational system for database management and is based on version 4.2 that was developed at the University of California at Berkeley IT department. has developed many concepts that have become available only in some commercial database systems much later. is an open-source successor of the original Berkeley code. It supports a large part of the SQL standard and offers many modern features, such as: Complex queries. External keys. Triggers. Transaction Integrity. Multi-version concurrency control. Because of its liberal license can be used, modified and distributed completely free for any purpose (private, academic or commercial). C. Oracle database 11g According to [3] Oracle Database 11g is a fullfeatured database manager for the needs of medium-sized companies. Within is an Oracle Application Express, a unique online development environment that enables rapid construction of a database using a web browser. It also supports Oracle Developer graphical tool for database development, which allows the developer to browse database objects by running SQL queries, SQL scripts and editing PL / SQL statements. Oracle Database 11g is well integrated with Visual Studio through Oracle Data Access components that allow the developer to easily build.net applications and Web services based on database MIPRO 2017/SP

2 III. COMPARISON OF A DBMS A. Comparison of basic data of DBMS The first comparison that we will make is the comparison of basic data for each. According to [7] below in the text is an overview of Table 1 which contains a comparison of basic data s. From the attached Table 1 we can see that and have the same developer, is the only commercial, is supported on the variety number of operating systems, even 9. Oracle supports most programming languages. In the table we mentioned some of the most popular programming languages, although there are lesser-known languages that Oracle supports. All s have ACID. B. Comparison of syntax The second comparison is the syntax between,, and which is shown in Table 2. The commands are creating two tables Manufacturer and Tires, the input of data in tables and queries that run against created tables and which are written according to the syntax of the corresponding. From Table 2, we can see that the difference in the syntax for each is negligible. All that is changed is just one word, and that is NUMBER, which reads NUMERIC for and. We tested the examples only with two data types (VARCHAR and NUMERIC) in this paper in the future work we will broaden the scope. Database model TABLE I. COMPARISON OF BASIC DATA Relational Relational Relational DBMS DBMS DBMS Global Development Group Developer Oracle Oracle Licence Open source Commercial Open source Supported OS Solaris, FreeBSD Solaris, HP- UX, AIX Solaris, HP- UX, Unix, FreeBSD, NetBSD, OpenBSD C, C#, C++, D, Haskell, Perl, PHP, C, C#, C++, Cobol, Fortran, Java, Python, Haskell, Java, Supported Ruby, JavaScript, programming Objectiv-C Lisp, Perl, languages PHP, Python, Ruby, Visual Basic, Objectiv-C Transactions ACID ACID ACID Source: [7].Net, C, C++, Java, Perl, Python, Tcl C. Data types The third comparison is the difference between the data types that a particular is using. For easier and more user-friendly presentation we will use Table 3. which shows a comparison of data types. Simillar (or corresponding) data types through all three s are shown in the same color. According to sources [4], [5] and [6] we pulled out all the essential information for the comparison of data types. Below we will describe the advantages and disadvantages of different s for certain types of data which they have or do not have. Data type ARRAY doesn't have, but the alternative that users of are using is the temporary table. All three s have CHAR - it is used because it is fast, space efficient and it is practical to use when the rows are the same or approximately the same length. The CHARACTER in is a longer version of CHAR, there is also a variant of CHARACTER SET binary for character data type. It causes the column to be made from the appropriate binary data types so that the char becomes a binary char, varchar becomes varbinary while the character in is a string of fixed size. DATE is supported in all three and it is used to save the date in the form of strings or numbers. CHARACTER VARYING is only supported in and its advantage over regular character is variable length. DECIMAL is supported in and, and also supports DEC. Oracle solves the lack of decimals in a way that converts decimal to numeric data type. In user precisely defines the decimal numbers ranging from figures before the decimal point and numbers after the decimal point. In decimal determines the exact number of digits before the decimal point and the number of digits after the decimal point. The maximum number of decimal digits is 65 while the number of supported decimals is 30. It also has an option that prevents unsigned negative values. DEC is synonymous for decimal. DOUBLE is supported in and. Alternative for the DOUBLE which is used by users of Oracle is BINARY_DOUBLE, and it is 64-bit floating point NUMBER or BINARY_FLOAT. In is used DOUBLE PRECISION, and it consists of 15 decimal numbers. In DOUBLE is the number with the moving point of normal size, a range can be less than that is specified in the documentation, but it all depends on the hardware and operating system. ENUM is supported in and, but in Oracle it isn't. ENUM is a string object with a selected list of allowed values that are listed in the column with specifications at the time of creating the table. ENUM is a data type that includes statically ordered set of values, and they are equivalent to ENUM type that is supported in many programming languages. In Oracle using PL / SQL users can make their own type that has a similar logic to Enum. MIPRO 2017/SP 1749

3 TABLE II. COMPARISON OF SYNTAX Commands CREATE TABLE 1 CREATE TABLE MANUFACTURER (ID_PRO VARCHAR (2) NOT NULL, PRO_NAME VARCHAR (20) NOT NULL, CREATE TABLE MANUFACTURER( ID_PRO VARCHAR (2) NOT NULL, PRO_NAME VARCHAR (20) NOT NULL, CREATE TABLE MANUFACTURER( ID_PRO VARCHAR (2) NOT NULL, PRO_NAME VARCHAR (20) NOT NULL, INSERT INTO TABLE 1 'GOODYEAR', 'BUFFALO'); 'GOODYEAR', 'BUFFALO'); 'GOODYEA', 'BUFFALO'); CREATE TABLE 2 PRICE NUMBER(6,2) NOT NULL, STOCK NUMBER NOT NULL, SOLD NUMBER NOT NULL); PRICE NUMERIC(6,2), STOCK NUMERIC NOT NULL, SOLD NUMERIC NOT NULL); PRICE NUMERIC(6,2), STOCK NUMERIC NOT NULL, SOLD NUMERIC NOT NULL); INSERT INTO TABLE 2 QUERY 1 ID_PRO IN (SELECT ID_PRO FROM MANUFACTURER WHERE HEADQUARTERS = 'MILANO'); ID_PRO IN (SELECT ID_PRO FROM MANUFACTURER WHERE HEADQUARTERS = 'MILANO'); ID_PRO IN (SELECT ID_PRO FROM MANUFACTURER WHERE HEADQUARTERS = 'MILANO'); QUERY 2 SELECT AVG(SOLD/22*PRICE)"Average daily earnings" SELECT AVG(SOLD/22*PRICE) "Average daily earnings" SELECT AVG(SOLD/22*PRICE) "Average daily earnings" FLOAT is not supported in. The alternative to FLOAT in is a REAL, DOUBLE PRECISION or NUMERIC. In FLOAT is the value of the approximate numerical value data with a movable section, and his precision is from 0 to 23 results in a 4-byte one-precision float column. FLOAT is a subtype of number data type and it has a precision in the range from 1 to 126 binary numbers. INT is supported only in. Oracle solves this problem so that INT converts into NUMBER data type. uses instead of INT use an INTEGER for values whose size of storage is 4 bytes and BIG INT for values that require storage size of 8 bytes. supports SQL standard integer types and the size of its storage is 4 bytes. LONG is supported only in Oracle. The columns that we declare as LONG can be stored as signs of adjustable length and a length is up to 2 gigabytes of information. alternative for LONG would be text that can store up to 4 gigabytes of character, and the effective maximum length is less if the value contains multibyte signs. also used TEXT data type as a replacement for LONG, and the size is undefined. TABLE III. Data Type COMPARISON OF DATA TYPES ARRAY CHAR CHARACTER DATE CHARACTER VARYING DECIMAL, DEC DOUBLE ENUM FLOAT INT LONG NUMBER NUMERIC RAW REAL TEXT TIME TIMESTAMP UUID VARCHAR VARCHAR YEAR MIPRO 2017/SP

4 NUMBER is supported only in Oracle. NUMBER is a data type that stores the numbers with a fixed and floating point, and their storage size is almost unlimited and works with 38 digits of precision. In alternatives that are used instead of the number are SMALLINT, BIGINT, DECIMAL, DOUBLE PRECISION, and NUMERIC. equivalent is the NUMERIC data type that allows the use of unsigned attributes that represent negative values, and signed is always given so there is no effect. NUMERIC is supported in and, its equivalent in Oracle is NUMBER. RAW is supported only in Oracle. RAW is variable-length binary or byte string. Full size is 2000 bytes and there must be given the value of the RAW size. alternative is a BIT. BIT is a kind of a bit field where M signifies the value of bits from 1 to 64, and the default value is 1 if M is not specified. alternative is BYTES. It allows storage of binary strings, and the size of the storage is from 1 to 4 bytes. and support the REAL. Alternative for REAL is a FLOAT in Oracle. REAL in works almost the same as FLOAT or DOUBLE PRECISION. REAL in has 6 decimal digits of precision, and storage size is 4 bytes. TEXT is not supported in Oracle, but the alternative in Oracle is long. TEXT in, in the beginning, had a TEXT data type, but when was transferred to SQL language for compatibility, instead of being renamed they added a new type VARCHAR, but both types use the same C routines internally. TIME is supported in and while in Oracle as an alternative is used a DATE. TIME in is a data type that can be used not only to represent the time of the day but also the elapsed time or the time interval between two events. In TIME data type saves the time of day. Storage size is 8 bytes. TIMESTAMP is supported in all three. TIMESTAMP in is a data type and is used for values that contain both DATE and TIME intervals. TIMESTAMP in has two variants, one is without time zone, and one is with the time zone, and both of them store date and time. TIMESTAMP in Oracle has three variants, the ordinary one, with the time zone and with local time of time zone. UUID is only supported in. UUID is written as a series of small hexadecimal digits through several groups separated by dashes, a separate group of eight digits followed by three groups of four digits followed by a group of 12 digits, and all that together is the thirty-two digits that represent one hundred and twenty-eight bits. In Oracle, the UUID is obtained using a function in PL / SQL, while in is used the UUID() function that returns the value of hundred and twenty-eight bit number as utf8 string of five hexadecimal numbers in the form of aaaaaaaa-bbbb-ccccdddd-eeeeeeeeeeee. VARCHAR is supported in all three. VARCHAR in is very similar to char, but the difference is in the storage and retrieval of data. VARCHAR is a string of variable length, and its length is from 0 to while its maximum effective length is limited to a maximum line length which is 65,535 bytes. VARCHAR in is the character type of general purpose variable length with a limit. VARCHAR in Oracle is the same as varchar, but it is recommended to use VARCHAR2 because the VARCHAR is designed to redefine in a separate data type. It will be used for variable length strings compared with different comparison semantics. VARCHAR2 is supported only in Oracle. VARCHAR2 is a data type that specifies the character string of variable length, once when the VARCHAR2 is created column has an available maximum number of characters or bytes of data that can be kept. The equivalent of VARCHAR2 in and is VARCHAR. YEAR is supported only in. YEAR is the data type of 1 byte and it is used to represent the values in the form yyyy, and the range is from 1901 to Oracle and use DATE data type instead. D. Speed performance In the last comparison we will compare the speed of execution of certain commands in each of the s. The hardware resources that were used during testing are: CPU: Intel (R) i5 2400K, RAM: 8GB DDR3 RAM, HDD: WD 1T, OS: Windows 7 64-bit. To view the runtime we used commands within the s. For Oracle, the commands are set timing on and set autotrace traceonly, and for is \timing, while for command was not necessary, because it already has that option within itself as part of the Workbench. We must mention that the speed comparison done in this paper is prety simple (with simple statements and simple database with small number of tuples). Table 4. shows our comparison of the speed performance of the simple queries. More comprehensive speed performance will be done in the future (with larger and more complex database, as well as more complex queries). In Table 4. we can see the results of comparing the speeds which will be described in more detail below. The first command create table was performed fastest by Oracle for only 0.03 ms. After Oracle was and it performed a query for 0.22 ms and at the end is. The second command insert into was performed fastest by Oracle for ms, followed by for ms and at the end is with 0.05 ms. The third query select was performed fastest by for ms, followed by Oracle with 0.01 ms and at the end is with 0.02 ms. The fourth query select was executed equally fast by both Oracle and for ms, while the performed it for ms. The fifth query join was performed equally fast by both and Oracle in a time of ms, while the performed it in ms. The sixth command update was performed fastest by Oracle for ms, followed by with ms and at the end is with 0.06 ms. The seventh and final command drop table was performed fastest by for 0.08 ms, followed by with 0.16 ms and at the end is Oracle with 0.44 ms. MIPRO 2017/SP 1751

5 TABLE IV. Commands and queries CREATE TABLE TIRES(ID_TIRES VARCHAR(6) NOT NULL,TIRES_NAME VARCHAR(30) NOT NULL,ID_PRO VARCHAR(2) NOT NULL,ABOVE_CLASS VARCHAR(6), PURPOSE VARCHAR(15) NOT NULL,PRICE NUMBER(6,2) NOT NULL,STOCK NUMBER NOT NULL,SOLD NUMBER NOT NULL); INSERT INTO TIRES VALUES ('GY3455', 'DURAGRIP', 'GY', NULL, 'LJETNE', , 12, 1567); SELECT NAZIV_TIRES, PURPOSE, PRICE FROM TIRES WHERE ID_PRO = 'MN' AND PURPOSE IN (SELECT PURPOSE FROM TIRES WHERE ID_PRO IN (SELECT ID_PRO FROM MANUFACTURER WHERE PRO_NAME='PIRELLI')); SELECT PRO_NAME, HEADQUARTERS FROM MANUFACTURER WHERE ID_PRO IN (SELECT ID_PRO FROM TIRES WHERE PURPOSE = 'LJETNE' GROUP BY ID_PRO); SELECT MANUFACTURER.ID_PRO, MANUFACTURER.PRO_NAM E,TIRES.TIRES_NAMEFROM MANUFACTURER INNER JOIN TIRES ON MANUFACTURER.ID_PRO=TI RES.ID_PRO; UPDATE TIRES SET NAZIV_TIRES='DURAGRIP1', STOCK=13 WHERE NAZIV_TIRES='DURAGRIP'; DROP TABLE TIRES; COMPARISON OF SPEED PERFORMANCE OF QUERIES IN IV. CONCLUSION Execution time in ms In this article we have compared 3 relational database management systems () -, and. They are compared according to the criteria that we defined, such as the comparison of basic data, syntax, data types and speed performance. At the very end, we will analyze each of the criteria by which we compared the systems for managing databases. The first criterion for comparing was the basic data of each of the 's. Each of them uses the relational model, and have an open source license, while Oracle license is commercial. Oracle databases are designed to be used when the large budget is available and they served to solve very complex problems in contrast to the and that are free to use. The number of supported operating systems for is five, for Oracle is 6, while supports up to 9 operating systems. The number of supported programming languages for is 11, for is 7, and Oracle supports 15 of them. In the first comparison Oracle and are dominating. The second criterion is the comparison between the syntax of 's. The syntax is the same in terms of create, insert, select, drop, join for all three, and the only difference appears in the writings of certain types of data and how the values within them are written. The third criterion of comparison of s is data types. We compared 22 types of data for each. For each of the systems, if there is no particular type of data supported, another type of data is supported, that performs multiple functions or has an alternative solution using a different data type or the combination of several. So on the basis of that, there is no best, it all depends on what a person who works with database management prefers to use. The fourth and last criterion of comparison is the speed performance of queries in s. According to Table 4. it can be seen that the speed of execution is prevailed by Oracle which is the best to use in large and complex systems, while immediately behind it is intended for free users, education and business, to the fact that is the most widely used open source system database management. is also very popular open source system for managing databases and it applies the same as, only it is much less prevalent in contrast to. After all the comparisons, Oracle would be the best option for, if to the user who uses it the speed and performance of complex operations is the most important thing and is willing to pay, while is our recommendation for the open source version which is slightly slower than the Oracle by the tests we made. However, we must state that our conclusions are based on a very simple databace and benchmark - more comprehensive syntax and data type comparison, as well as speed performance will be done in the future (with larger and more complex database, as well as more complex queries). REFERENCES [1], Enterprise Edition.:, [Online]. [2], Documentation.:, [Online]. [3] Westcon, Oracle Database 11g Standard Edition with real application clusters.: Westcon, [Online]. [4], 5.7 Reference Manual: Data Types.:, [Online]. [5] Oracle Help Center, Database SQL Language Reference: Datatypes.: Oracle Help Center, [Online]. ments001.htm [6] TutorialsPoint, Data Types.: TutorialsPoint, [Online]. m [7] DB-Engines, System Properties Comparison vs. Oracle SQL vs..: DB-Engines, [Online]. [ ] [8] R. Manger, Baze podataka. Zagreb, Element [2012]. [Online]. [ ] 1752 MIPRO 2017/SP