SQL Syntax
SQL follows some unique set of rules and guidelines called syntax. Here, we are providing all the basic SQL syntax.
- SQL is not case sensitive. Generally SQL keywords are written in uppercase.
- SQL statements are dependent on text lines. We can place a single SQL statement on one or multiple text lines.
- You can perform most of the action in a database with SQL statements.
- SQL depends on relational algebra and tuple relational calculus.
Various Syntax in SQL
SQL statements are started with any of the SQL commands/keywords like SELECT, INSERT, UPDATE, DELETE, ALTER, DROP etc. and the statement ends with a semicolon (;).
All the examples given in this tutorial have been tested with a MySQL server.
SQL SELECT Statement
SELECT column1, column2....columnN
FROM table_name;
SQL DISTINCT Clause
SELECT DISTINCT column1, column2....columnN
FROM table_name;
SQL WHERE Clause
SELECT column1, column2....columnN
FROM table_name
WHERE CONDITION;
SQL AND/OR Clause
SELECT column1, column2....columnN
FROM table_name
WHERE CONDITION-1 {AND|OR} CONDITION-2;
SQL IN Clause
SELECT column1, column2....columnN
FROM table_name
WHERE column_name IN (val-1, val-2,...val-N);
SQL BETWEEN Clause
SELECT column1, column2....columnN
FROM table_name
WHERE column_name BETWEEN val-1 AND val-2;
SQL LIKE Clause
SELECT column1, column2....columnN
FROM table_name
WHERE column_name LIKE { PATTERN };
SQL ORDER BY Clause
SELECT column1, column2....columnN
FROM table_name
WHERE CONDITION
ORDER BY column_name {ASC|DESC};
SQL GROUP BY Clause
SELECT SUM(column_name)
FROM table_name
WHERE CONDITION
GROUP BY column_name;
SQL COUNT Clause
SELECT COUNT(column_name)
FROM table_name
WHERE CONDITION;
SQL HAVING Clause
SELECT SUM(column_name)
FROM table_name
WHERE CONDITION
GROUP BY column_name
HAVING (arithematic function condition);
SQL CREATE TABLE Statement
CREATE TABLE table_name(
column1 datatype,
column2 datatype,
column3 datatype,
.....
columnN datatype,
PRIMARY KEY( one or more columns )
);
SQL DROP TABLE Statement
SQL CREATE INDEX Statement
CREATE UNIQUE INDEX index_name
ON table_name ( column1, column2,...columnN);
SQL DROP INDEX Statement
ALTER TABLE table_name
DROP INDEX index_name;
SQL DESC Statement
SQL TRUNCATE TABLE Statement
TRUNCATE TABLE table_name;
SQL ALTER TABLE Statement
ALTER TABLE table_name {ADD|DROP|MODIFY} column_name {data_ype};
SQL ALTER TABLE Statement (Rename)
ALTER TABLE table_name RENAME TO new_table_name;
SQL INSERT INTO Statement
INSERT INTO table_name( column1, column2....columnN)
VALUES ( value1, value2....valueN);
SQL UPDATE Statement
UPDATE table_name
SET column1 = value1, column2 = value2....columnN=valueN
[ WHERE CONDITION ];
SQL DELETE Statement
DELETE FROM table_name
WHERE {CONDITION};
SQL CREATE DATABASE Statement
CREATE DATABASE database_name;
SQL DROP DATABASE Statement
DROP DATABASE database_name;
SQL USE Statement
SQL COMMIT Statement
SQL ROLLBACK Statement
