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Apache Derby – Syntax



This chapter gives you the syntax of all the Apache Derby SQL statements.

All the statements start with any of the keywords like SELECT, INSERT, UPDATE, DELETE, ALTER, DROP, CREATE, USE, SHOW and all the statements end with a semicolon (;).

The SQL statements of Apache Derby are case in sensitives including table names.

CREATE Statement

CREATE TABLE table_name (
   column_name1 column_data_type1 constraint (optional),
   column_name2 column_data_type2 constraint (optional),
   column_name3 column_data_type3 constraint (optional)
);

DROP TABLE

DROP TABLE table_name;

INSERT Statement

INSERT INTO table_name VALUES (column_name1, column_name2, ...);

SELECT Statement

SELECT column_name, column_name, ... FROM table_name;

UPDATE Statement

UPDATE table_name
   SET column_name = value, column_name = value, ...
   WHERE conditions;

DELETE Statement

DELETE FROM table_name WHERE condition;

DESCRIBE Statement

Describe table_name

SQL TRUNCATE TABLE Statement

TRUNCATE TABLE table_name;

ALTER Statement – Adding column

ALTER TABLE table_name ADD COLUMN column_name column_type;

ALTER Statement – Adding constraint

ALTER TABLE table_name ADD CONSTRAINT constraint_name constraint (column_name);

ALTER Statement – Dropping column

ALTER TABLE table_name DROP COLUMN column_name;

ALTER Statement – Dropping constraint

ALTER TABLE table_name DROP CONSTRAINT constraint_name;

WHERE Clause

SELECT * from table_name WHERE condition;
or,
DELETE from table_name WHERE condition;
or,
UPDATE table_name SET column_name = value WHERE condition;

GROUP BY Clause

SELECT column1, column2, . . . table_name GROUP BY column1, column2, . . .;

ORDER BY Clause

SELECT * FROM table_name ORDER BY column_name ASC|DESC.

Having Clause

SELECT column1, column2 . . . from table_name GROUP BY column having
condition;

Creating Index

CTREATE INDEX index_name on table_name (column_name);

Creating an UNIQUE index

CREATE UNIQUE INDEX index_name on table_name (column_name);

Creating a COMPOSITE index

CREATE INDEX index_name on table_name (column_name1, column_name2);

Displaying the Indexes

SHOW INDEXES FROM table_name;

Dropping Indexes

DROP INDEX index_name;

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