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Show date like 30-04-2020 instead of 2020-04-30 from MySQL database?

AmitDiwan
AmitDiwan
Updated on 11-Dec-2020 131 Views

For this, use DATE_FORMAT() in MySQL. The syntax is as follows −Exampleselect date_format(yourColumnName, '%d-%m-%Y') as anyAliasName from yourTableName;Let us create a table −Examplemysql> create table demo80    -> (    -> due_date date    -> ); Query OK, 0 rows affected (0.74Insert some records into the table with the help of insert command −Examplemysql> insert into demo80 values('2020-04-30'); Query OK, 1 row affected (0.14 mysql> insert into demo80 values('2016-01-10'); Query OK, 1 row affected (0.17 mysql> insert into demo80 values('2018-03-21'); Query OK, 1 row affected (0.12Display records from the table using select statement −Examplemysql> select *from demo80;This will ...

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How to get username using ID from another table in MySQL database?

AmitDiwan
AmitDiwan
Updated on 11-Dec-2020 3K+ Views

To get username using ID from two tables, you need to use JOIN and join the tables.Let us create a table −Examplemysql> create table demo77    -> (    -> userid int not null primary key,    -> username varchar(20)    -> ); Query OK, 0 rows affected (2.63Insert some records into the table with the help of insert command −Examplemysql> insert into demo77 values(1, 'John'); Query OK, 1 row affected (0.19 mysql> insert into demo77 values(2, 'Bob'); Query OK, 1 row affected (0.36Display records from the table using select statement −Examplemysql> select *from demo77;This will produce the following ...

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Find all users with a unique last name in MySQL?

AmitDiwan
AmitDiwan
Updated on 11-Dec-2020 640 Views

To find all users with unique last name, use GROUP BY HAVING COUNT().Let us create a table −Examplemysql> create table demo76    -> (    -> firstName varchar(20),    -> lastName varchar(20)    -> ); Query OK, 0 rows affected (9.29Insert some records into the table with the help of insert command −Examplemysql> insert into demo76 values('John', 'Doe'); Query OK, 1 row affected (2.52 mysql> insert into demo76 values('David', 'Smith'); Query OK, 1 row affected (6.31 mysql> insert into demo76 values('Adam', 'Smith'); Query OK, 1 row affected (1.52Display records from the table using select statement −Examplemysql> select *from ...

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Fetching rows updated at timestamp older than 1 day in MySQL?

AmitDiwan
AmitDiwan
Updated on 11-Dec-2020 959 Views

For this, yYou can use from_unixtime() along with now().Let us create a table with some data type −Examplemysql> create table demo75    -> (    -> due_date int(11)    -> ); Query OK, 0 rows affected, 1 warning (2.87Insert some records into the table with the help of insert command −Examplemysql> insert into demo75 values(unix_timestamp("2020-01-10")); Query OK, 1 row affected (0.46 mysql> insert into demo75 values(unix_timestamp("2020-11-19")); Query OK, 1 row affected (0.59 mysql> insert into demo75 values(unix_timestamp("2020-12-18")); Query OK, 1 row affected (0.44 mysql> insert into demo75 values(unix_timestamp("2020-11-10")); Query OK, 1 row affected (0.70Display records from the ...

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MySQL LIKE query with dynamic array?

AmitDiwan
AmitDiwan
Updated on 11-Dec-2020 2K+ Views

To implement LIKE query with dynamic array, the syntax is as follows −Exampleselect *from yourTableName    where yourColumnName2 like "%yourValue%"    order by yourColumnName1 asc    limit yourLimitValue;Let us create a table −Examplemysql> create table demo74    -> (    -> user_id int not null auto_increment primary key,    -> user_names varchar(250)    -> )    -> ; Query OK, 0 rows affected (0.67Insert some records into the table with the help of insert command −Examplemysql> insert into demo74(user_names) values("John Smith1, John Smith2, John Smith3"); Query OK, 1 row affected (0.18 mysql> insert into demo74(user_names) values("John Smith1"); Query OK, ...

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What is the purpose and usage of "FOR UPDATE OF" clause in a COBOL-DB2 program

Mandalika
Mandalika
Updated on 01-Dec-2020 5K+ Views

Problem: What is the purpose of the "FOR UPDATE OF" clause in a cursor? What will happen if we fire an UPDATE statement without using this clause in a COBOL-DB2 program?SolutionThe “FOR UPDATE OF” clause is given in the cursor declaration and it is used when we want to update the table. All the columns which need to be updated should be given in the cursor declaration.The “FOR UPDATE OF” clause will place the exclusive lock on all the qualifying rows once the cursor is open. We can also update the table without using “FOR UPDATE CLAUSE” but in that ...

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What is update operation on the cursor having JOIN between 2 tables?

Mandalika
Mandalika
Updated on 01-Dec-2020 829 Views

Problem: Is it possible to update a CURSOR in which we have used JOIN on 2 tables ORDERS and TRANSACTIONS? Why or why not? How can we proceed to UPDATE any of these tables?SolutionWhenever we use JOIN in a cursor on two or more tables (ORDERS and TRANSACTIONS in this case) a temporary table is generated in the virtual memory. However, since this is a temporary table we can fetch data from this table but it is not possible to update this table.If we want to update any of the tables used in the JOIN then we have to declare ...

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What is the execution result when non-SQL changes are made in the program without BIND?

Mandalika
Mandalika
Updated on 01-Dec-2020 320 Views

Problem: A COBOL-DB2 program is changed to increase the length of a variable from PIC X(5) to PIC X(8). However, there are no changes in the SQL of the program. What will be the result if the program's plan/package is not binded for these changes?SolutionThe variable length change from PIC X(5) to PIC X(8) is not a DB2 change and there are no modifications required for SQL statements in the program. However, still we need to BIND its PLAN/PACKAGE else we will get SQL error code -818 which states that “THE PRECOMPILER-GENERATED TIMESTAMP x IN THE LOAD MODULE IS DIFFERENT ...

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How to bind multiple versions of a DB2 program into a package?

Mandalika
Mandalika
Updated on 01-Dec-2020 1K+ Views

Packages are DB2 database objects which hold the executable forms of SQLs which are used in COBOL-DB2 programs. The packages are stored in a catalog table and contain the strategy/tables/columns/predicate associated with the SQL statements.If there is a DB2 table ORDERS_TEST in test environment and ORDERS_PROD in production environment, then we need two versions of COBOL-DB2 program (which will access these tables) — one for test and the other for production.Although both programs will be carbon copy of each other, the only difference lies in the SQL statements. The test version of the program will use table ORDERS_TEST in SQL ...

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What will be the result if there is a timestamp mismatch in the DBRM and Load module?

Mandalika
Mandalika
Updated on 01-Dec-2020 996 Views

When the COBOL-DB2 source code is given as an input in the pre-compilation stage, we get 2 important components — DBRM and modified source code.In modified source code, the SQL statements are replaced by COBOL calls and the DBRM contains all the SQL statements which are present in the COBOL-DB2 program. The pre-compiler inserts the timestamp in both DBRM and modified source code.In case of DBRM bind directly to the plan, the system compares the timestamp of the DBRM and load module when the COBOL-DB2 program is executed. In case there is a mismatch in the timestamp the JCL step ...

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