Using lock table, PL-SQL Programming

Assignment Help:

Using LOCK TABLE

You use the LOCK TABLE statement to lock the whole database tables in the specified lock mode so that you can share or deny the access to them. For illustration, the statement below locks the emp table in the row share mode. The Row share locks permit concurrent access to the table; they avoid other users from locking the whole table for the restricted use. The Table locks are released when your transaction issues a commit or rollback.

LOCK TABLE emp IN ROW SHARE MODE NOWAIT;

The lock mode determines what other locks can be located on the table. For illustration, many users can obtain the row share locks on the table at the same time, excluding only one user at a time can obtain an exclusive lock. Whereas one user has an exclusive lock on the table, no other users can insert, delete, and update rows in that table.


Related Discussions:- Using lock table

Definition of from - sql, Definition of FROM - SQL Recall that the ope...

Definition of FROM - SQL Recall that the operand of FROM is denoted by a commalist, each element of that commalist being a table expression optionally accompanied by a range v

Keys in sql, Keys in SQL SQL support for keys in the following respect...

Keys in SQL SQL support for keys in the following respects: SQL does not require at least one key for every base table. If no key is explicitly declared, then KEY {ALL B

Updating variables, Updating Variables For assignment, SQL uses the ke...

Updating Variables For assignment, SQL uses the key word SET, as in SET X = X + 1 (read as "set X equal to X+1") rather than X: = X + 1 as found in many computer languages.

Join query, Using a join on 3 tables, select 5 columns and 10 rows from the...

Using a join on 3 tables, select 5 columns and 10 rows from the 3 tables without the use of a Cartesian product Query: SELECT E.LAST_NAME, E.FIRST_NAME, S.BUILDING, S.BRAN

Theory of spontaneous generation - origin of life, THEORY OF SPONTANEOUS GE...

THEORY OF SPONTANEOUS GENERATION - ABIOGENESIS OR AUTOGENESIS - According to this theory, the existing living communities have originated from non-living organic matter with

Sql script to create and populate the tables, Create the four tables and po...

Create the four tables and populate them with the given data. Answer the following queries in SQL. 1. Get all part-color/part-city combinations. Note: Here and subsequently, the

What is a record, What Is a Record  ? A record is a group of related...

What Is a Record  ? A record is a group of related data items that stored in the fields, each with its own name and datatype. Assume that you have different data about an em

Using not null-declarations in sql, Using NOT NULL Besides assigning an ...

Using NOT NULL Besides assigning an initial value, the declarations can impose the NOT NULL constraint, as the example below shows: acct_id INTEGER(4) NOT NULL := 9999; You ca

Using default-declarations in sql, Using DEFAULT You can use the keyword...

Using DEFAULT You can use the keyword DEFAULT rather than that of the assignment operator to initialize the variables. For e.g. the declaration blood_type CHAR := ’O’; it can b

Long and long raw in pl/sql, LONG and LONG RAW You use the LONG datatyp...

LONG and LONG RAW You use the LONG datatype to store the variable-length character strings. The LONG datatype is such as the VARCHAR2 datatype, except that the maximum length o

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd