My. SQL SQL Syntax and Use My.SQL Naming Rules.Get down and dirty with my.SQL by learning the basics of SQL syntax and useful functions for maintaining tables and integrity.This chapter is from the book Fluency with SQL is necessary for effective communication with the My.SQL. server, because that is the language that it understands.For example, when you.SQL statements to the server to be executed.You must also know SQL.My. SQL interface provided by your programming.SQL statements to it.Chapter 1, Getting Started with My.SQL and SQL, presented a.My. SQLs capabilities.This chapter builds.SQL implemented by.Retrieves the number of rows from a result set.This command is only valid for statements like SELECT or SHOW that return an actual result set.Php Sql Update Multiple Rows At Once' title='Php Sql Update Multiple Rows At Once' />My.SQL. It discusses how to refer to elements of databases, including the rules.It also describes.SQL statements that are used for the following types.Creating and destroying databases, tables, and indexes.Obtaining information about your databases and tables.Retrieving data using joins, subselects, and unions.Using multiple table deletes and updates.Performing transactions that allow multiple statements to be treated as a.Setting up foreign key relationships.Using the FULLTEXT search engine.Php Sql Update Multiple Rows At Once' title='Php Sql Update Multiple Rows At Once' />My.SQLs SQL statements can be grouped into several broad categories.Table 3. 1 lists some representative statements for each.In some cases, a.For example, mysqlshow allows SHOW operations to be.This chapter points out such equivalences where.Some of the statements in the table are not covered here because they are.Sphinx is a fulltext search engine, publicly distributed under GPL version 2.Commercial licensing eg.Php Sql Update Multiple Rows At Once' title='Php Sql Update Multiple Rows At Once' />For example, the administrative.GRANT and REVOKE for setting up user privileges are.Chapter 1. 1, General My.SQL Administration.Chapter 1. Security, provides further details on what privileges are available.The syntax for all SQL statements implemented by My.SQL is. listed in Appendix D, SQL Syntax Reference.In addition, you should.My. SQL Reference Manual for additional information, especially for. Free Smtp Server Windows 7 . My. SQL. Table 3.Types of SQL Statements Supported by My.I have multiple set of data to insert at once, say 4 rows.My table has three columns Person, Id and Office.INSERT INTO MyTable VALUES John, 123, Lloyds Office.Once we run that query, what exactly goes on behind the scenes to find employees who are named Jesus Well, the database software would literally have to look at.SQLSelecting, Creating, Dropping, and Altering Databases.USECREATE DATABASEDROP DATABASEALTER DATABASECreating, Altering, and Dropping Tables and Indexes.CREATE TABLEDROP TABLECREATE INDEXDROP INDEXALTER TABLEGetting Information About Databases and Tables.DESCRIBESHOWRetrieving Information from Tables.SELECTUNIONPerforming Transactions.BEGINCOMMITROLLBACKSET AUTOCOMMITModifying Information in Tables.DELETEINSERTLOAD DATAREPLACEUPDATEAdministrative Statements.FLUSHGRANTREVOKEThe final section of the chapter describes what My.SQL does not. includethat is, what features it lacks.These are capabilities found in.My. SQL. Such features include triggers, stored.Do these omissions mean that My.SQL isnt a. real database system Some people think so, but in response.Ill simply observe that the lack of these capabilities in My.SQL. hasnt stopped large numbers of people from using it.Thats probably. because for many or most applications, those features dont matter.I should also point out that the set of features missing from My.SQL continues. to shrink over time.For the first edition of this book, the list of missing.A significant amount of progress has been made in improving My.SQL. since then, and those capabilities all have been added now.Triggers, stored.Almost every SQL statement refers in some way to a database or its.This section describes the syntax rules for referring to.Names are subject to case.Referring to Elements of Databases.When you use names to refer to elements of databases, you are constrained by.The form of names.Another factor that affects.Legal characters in names.Unquoted names can consist of any alphanumeric.Names can start with any.However, a name cannot.My. SQLs support for names that begin with a number is somewhat.If you use such a name, be particularly careful.E or e because. For example, the expression.Does it mean the same thing, or is it a number in scientific notation Aliases can be fairly arbitrary, but you should quote an alias within.SQL keyword, is entirely numeric, or.As of My. SQL 3. 2.ASCII 0, and ASCII 2.This is useful when a name contains special characters or is a reserved.Quoting a name also allows it to be entirely numeric, something that.There are also two additional constraints for database and table names.First, you cannot use the.Second, you cannot.UNIX or Windows pathname separator characters.The separator characters are disallowed in database.Consequently, these.The UNIX pathname separator is disallowed on Windows.For example, suppose you were allowed.Windows. That would make it impossible.UNIX, because filenames on that platform cannot contain.Name length. Names for databases, tables, columns, and indexes can.Alias names can be up to 2.Name qualifiers. Depending on context, a name may need to be qualified.To refer to a database, just specify.USE dbname. SHOW TABLES FROM dbname To refer to a table, you have two choices.First, a fully qualified table.SHOW TABLES FROM dbname.SELECT FROM dbname.Second, a table name by itself refers to a table in the default current.If sampdb is the default database, the following statements.SELECT FROM member.SELECT FROM sampdb.If no database has been selected, naming a table without a database qualifier.To refer to a column, there are three choices fully qualified, partially.A fully qualified name written as dbname.A partially qualified name written as tblname.An unqualified name written simply.The following two queries refer to the same pair of.FROM clause of each.SELECT lastname, firstname FROM president.SELECT lastname, firstname FROM members Its usually unnecessary to supply fully qualified names, although.If you select a database with.USE statement, that database becomes the default database and.If youre using a.SELECT statement that refers to only one table, that table is implicit.Its necessary to qualify.For. example, if a query refers to tables from multiple databases, any table.My. SQL know which database to look in to find the table.Similarly. if a query uses multiple tables and refers to a column name that is present.Server startup mode.If the server has been started with the ansi.ANSIQUOTES option, names can be quoted with double.Case Sensitivity in SQL Statements.Case sensitivity rules in SQL statements vary for different parts of the.SQL keywords and function names.Keywords and function names are.They can be given in any lettercase.The following statements.SELECT NOW. s. El.Ec. T n. Ow Database and table names.Databases and tables in My.SQL are implemented.As a result, case sensitivity of database and table names depends on the way.Windows filenames are.Windows does not treat database.Servers running on UNIX usually treat database.UNIX filenames are case sensitive.An exception is that names in HFS file systems under Mac OS X are not case.You should consider lettercase issues if you create a database on a server.For example, if you create.ABC on a UNIX server where those.Windows machine there, abc and ABC would not be.One way to avoid having.Then case of names wont be a problem if you move.Another approach to issues of name lettercase.This variable is discussed further in Chapter 1.The My. SQL Data.Directory. Column and index names.Column and index names are not case sensitive.My. SQL. The following queries are equivalent SELECT name FROM student.SELECT NAME FROM student.SELECT n. Am. E FROM student Alias names.Aliases are case sensitive.You can specify an alias.Regardless of whether or not a database or table name is case sensitive on.That is not true for SQL keywords, function names, or column and index.Naturally, the query will be more readable if you use a consistent.Sel. ECt Nam. E Fr.
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