<< < 25 26 27 28 29 30 31 32 33 34 35 > >>   ∑:1354  Sort:Date

Logical Operations in PL/SQL in Oracle
What Are the Logical Operations in Oracle? PL/SQL supports 3 logical operations as shown in the following sample script: PROCEDURE proc_comparison AS x BOOLEAN := TRUE; y BOOLEAN := FALSE; res BOOLEAN; BEGIN res = x AND y; res = x OR y; res = NOT x; -- more statements END;   ⇒ Categories of Data Typ...
2018-08-06, 2513🔥, 0💬

Introduction to SQL Basics in MySQL
Where to find answers to frequently asked questions on Introduction to SQL Basics in MySQL? Here is a list of frequently asked questions and their answers compiled by FYIcenter.com DBA team on Introduction to SQL Basics in MySQL. Clear answers are provided with tutorial exercises on character and nu...
2018-04-21, 2513🔥, 0💬

Call a Sub Procedure in Oracle
How To Call a Sub Procedure in Oracle? To call a sub procedure, just use the sub procedure name as a statement. Here is another example of calling a sub procedure: SQL&gt; CREATE OR REPLACE PROCEDURE WELCOME AS 2 PROCEDURE WELCOME_PRINT(S CHAR) AS 3 BEGIN 4 DBMS_OUTPUT.PUT_LINE('Welcome to ' || ...
2018-10-26, 2510🔥, 0💬

Add a New Column to an Existing Table in Oracle
How To Add a New Column to an Existing Table in Oracle? If you have an existing table with existing data rows, and want to add a new column to that table, you can use the ALTER TABLE ... ADD statement to do this. Here is an example script: SQL&gt; connect HR/fyicenter Connected. SQL&gt; CREA...
2019-05-25, 2509🔥, 0💬

Rename a Column in an Existing Table in Oracle
How To Rename a Column in an Existing Table in Oracle? Let's say you have an existing with an existing column, but you don't like the name of that column, can you rename that column name? The answer is yes. You can use the ALTER TABLE ... RENAME COLUMN statement to do this. See the following SQL scr...
2019-05-25, 2508🔥, 0💬

Empty Your Recycle Bin in Oracle
How To Empty Your Recycle Bin in Oracle? If your recycle bin is full, or you just want to clean your recycle bin to get rid of all the dropped tables, you can empty it by using the PURGE statement in two formats: PURGE RECYCLEBIN - Removes all dropped tables from your recycle bin. PURGE TABLE table_...
2019-05-10, 2508🔥, 0💬

List Table Names with "mysqlshow" Command in MySQL
How To Show Table Names with "mysqlshow" in MySQL? If you want to show table names with "mysqlshow", you need to specify a database name. The followings tutorial exercise shows you how to get all table names that match a pattern: If you want analyze tables with "mysqlcheck", you need to use the "--a...
2018-05-19, 2508🔥, 0💬

Use "IF" Statements with Multiple Conditions in Oracle
How To Use "IF" Statements on Multiple Conditions in Oracle? If you have multiple blocks of codes to be executed based on different conditions, you can use the "IF ... ELSIF" statement. Here is a sample script on IF statements: DECLARE day VARCHAR2; BEGIN day := 'SUNDAY'; IF day = 'THURSDAY' THEN DB...
2018-07-13, 2506🔥, 0💬

Inner Join with the WHERE Clause in Oracle
How To Write an Inner Join with the WHERE Clause in Oracle? If you don't want to use the INNER JOIN ... ON clause to write an inner join, you can put the join condition in the WHERE clause as shown in the following query example: SQL&gt; SELECT d.department_name, e.first_name, e.last_name 2 FROM...
2019-10-18, 2504🔥, 0💬

Oracle Tablespace - Unit of Logical Storage in Oracle
What Is an Oracle Tablespace in Oracle? An Oracle tablespace is a big unit of logical storage in an Oracle database. It is managed and used by the Oracle server to store structures data objects, like tables and indexes.   ⇒ Oracle Data File - Unit of Physical Storage in Oracle ⇐ Managing Oracle Tab...
2019-04-17, 2502🔥, 0💬

Different Types of PL/SQL Code Blocks in Oracle
What Are the Different Types of PL/SQL Code Blocks in Oracle? There are 3 types of PL/SQL code blocks: Anonymous Block - A block of codes with no name. It may contain a declaration part, an execution part, and exception handlers. Stored Program Unit - A block of codes with a name. It is similar to a...
2018-11-29, 2502🔥, 0💬

Extract Unit Values from a Date and Time in MySQL
How To Extract a Unit Value from a Date and Time in MySQL? If you want to extract a specific date or time unit value out of a date or a time, you can use the EXTRACT(unit FROM expression) function. The tutorial exercise below gives you some good examples: ELECT EXTRACT(DAY FROM NOW()) FROM DUAL; 28 ...
2018-03-13, 2502🔥, 0💬

Privilege Needed to Connect to Oracle Server in Oracle
What Privilege Is Needed for a User to Connect to Oracle Server in Oracle? Oracle deny connection to users who has no CREATE SESSION privilege. Try the following tutorial exercise, you will find out how Oracle denies connection: &gt;.\bin\sqlplus /nolog SQL&gt; connect SYSTEM/fyicenter SQL&a...
2019-07-09, 2501🔥, 0💬

Creating User Defined Functions with Parameters in SQL Server
How To Create User Defined Functions with Parameters in SQL Server Transact-SQL? Very often, you need to create a function with one or more parameters so that the function can be more generic. You only supply values to those parameters at the time of executing the function. User defined functions wi...
2016-12-18, 2501🔥, 0💬

Data Pump Import Utility in Oracle
What Is the Data Pump Import Utility in Oracle? Oracle Data Pump Import utility is a standalone programs that allows you to import data objects from an Oracle dump file set into Oracle database. Oracle dump file set is written in a proprietary binary format by the Data Pump Export utility. Import ca...
2016-10-15, 2501🔥, 0💬

odbc_exec() - Executing SQL Statements
How To Execute a SQL Statement using odbc_exec()? Once you have created an ODBC connection object, you can use the odbc_exec() function to send a SQL statement to the SQL Server linked to the connection object for execution. Here is a simple PHP script that creates a new schema and a new table: &...
2024-06-30, 2500🔥, 0💬

Add a New Column to an Existing Table in MySQL
How To Add a New Column to an Existing Table in MySQL? If you have an existing table with existing data rows, and want to add a new column to that table, you can use the "ALTER TABLE ... ADD COLUMN" statement. The tutorial script below shows you a good example: mysql&gt; ALTER TABLE tip ADD COLU...
2018-03-04, 2499🔥, 0💬

Differences of CHAR and VARCHAR in SQL Server Transact-SQL
What Are the Differences between CHAR and VARCHAR in SQL Server Transact-SQL? CHAR and VARCHAR are both used to store code page based 1-byte character strings in Transact-SQL. But they have the following main differences: CHAR(n) stores character strings with a fixed length, n bytes, storage format....
2017-04-04, 2499🔥, 0💬

Use Values from Other Tables in UPDATE in Oracle
How To Use Values from Other Tables in UPDATE Statements in Oracle? If you want to update values in one with values from another table, you can use a subquery in the SET clause. The subquery should return only one row for each row in the update table that matches the WHERE clause. The tutorial exerc...
2020-01-21, 2497🔥, 0💬

Convert Character Strings to Times in Oracle
How To Convert Character Strings to Times in Oracle? You can convert dates to characters using the TO_CHAR() function as shown in the following examples: SELECT TO_CHAR(TO_DATE('04:49:49', 'HH:MI:SS'), 'DD-MON-YYYY HH24:MI:SS') FROM DUAL; -- Default date is the first day of the current month 01-MAY-...
2019-12-02, 2497🔥, 0💬

Tables Using MyISAM Storage Engine in MySQL
How To Create a New Table Using MyISAM Storage Engine in MySQL? MyISAM storage engine is based on the ISAM (Indexed Sequential Access Method) concept, which was first developed at IBM to store and retrieve data on secondary storage systems like tapes. MyISAM storage engine offers fast data storage a...
2017-09-12, 2497🔥, 0💬

Start Oracle SQL Developer in Oracle
How To Start Oracle SQL Developer in Oracle? To start Oracle SQL Developer, go to \sqldeveloper and click sqldeveloper.exe. The Oracle SQL Developer window shows up. Your copy of Oracle SQL Developer is running now. There will nothing under the Connections icon, because you haven't defined any conne...
2019-02-05, 2496🔥, 0💬

Start Oracle SQL Developer in Oracle
How To Start Oracle SQL Developer in Oracle? To start Oracle SQL Developer, go to \sqldeveloper and click sqldeveloper.exe. The Oracle SQL Developer window shows up. Your copy of Oracle SQL Developer is running now. There will nothing under the Connections icon, because you haven't defined any conne...
2019-02-05, 2496🔥, 0💬

What Is a Dead Lock in MySQL
What Is a Dead Lock in MySQL? A dead lock is phenomenon happens between two transactions with each of them holding a lock that blocks the other transaction as shown in the following diagram: (transaction 1) (transaction 2) update row X to create lock 1 update row Y to create lock 2 update row X (blo...
2017-04-28, 2496🔥, 0💬

<< < 25 26 27 28 29 30 31 32 33 34 35 > >>   ∑:1354  Sort:Date