In our Last SQL Tutorial, we discussed the basic concepts of SQL, Like What SQL is, and its future. And in this tutorial, we will learn the SQL Syntax concepts in detail. Because if your basics on SQL Syntax are clear, it helps you understand the SQL statements.
SQL (Structured Query Language) is a programming language mainly used to manage and manipulate relational databases. So when you want to perform some operation on the data available on the database, you have to write a query for that, and that SQL query should follow the predefined SQL syntax.
If the user is not writing the SQL syntax correctly, then the Query will not be executed, and the SQL server will give you an error message. So to get the requested records retrieved from the target database, you have to write the query in the correct SQL syntax.
SQL Syntax Key Points to Remember
Also, while writing the SQL queries, you have to keep in mind the below important points:
- In a SQL statement, the first word will always be a Keyword.
- SQL keywords are the words that have a specific meaning in the SQL language, such as SELECT, FROM, WHERE, etc. These keywords can be written in both uppercase and lowercase letters, but it is common practice to write them in uppercase to improve the readability of the SQL query. This is because uppercase letters stand out more than lowercase letters and make it easier to identify the keywords in the query.
- SQL syntax must end with a Semicolon (;).
- SQL statements or syntax are dependent on text lines. This means an SQL statement’s structure and format are determined by how it is written on the text lines. A single SQL statement can be written on one or multiple text lines, affecting how it is executed. For example, a single SQL statement written on one line will be executed as a single statement. In contrast, a single SQL statement written on multiple lines will be executed as separate statements.
- SQL is a powerful and versatile language that can perform a wide range of actions on a database. With SQL statements, you can create, modify, and delete databases, tables, and other objects and insert, update, and retrieve data from the database. SQL is also used to set permissions and manage users and user groups.
- SQL syntax is based on mathematical concepts called relational algebra and tuple relational calculus. These concepts define the relationships between data in a database and the operations that can be performed on that data. This means that the SQL language is designed to work with data in a structured, relational way, allowing users to manipulate and query the data logically and mathematically.
- SQL is not case-sensitive, meaning the SQL keywords and commands do not have to be entered in a specific case (uppercase or lowercase) to be recognized and executed by the database management system.
This feature of SQL can make it more user-friendly and convenient for developers and QA’s, as they do not have to worry about the case of their SQL keywords and commands. It also allows for more flexibility when writing SQL statements, as developers can use the case they prefer or that is most legible. - When creating table and column names, be sure to use lowercase letters. If you need to use multiple words, you can separate them with an underscore (_) or camelCase.
- If you are working with any String, you need to use single quotes (‘ ‘);
- And during working with numeric values, they should not be enclosed in quotes.
- While working with dates, the date format should be in “YYYY-MM-DD” format, and date values should be enclosed by single quotes (‘ ‘).
Remember that the SQL syntax may vary slightly depending on your specific database management system.
SQL Syntax Commands
Below we have listed down all the SQL syntax of various SQL commands. But we will discuss all of those SQL commands in detail and learn how to use those efficiently.
Select Statement
SELECT "column_name" FROM "table_name";
Distinct
SELECT DISTINCT "column_name" FROM "table_name";
Where;
SELECT "column_name" FROM "table_name" WHERE "condition"
And/Or
SELECT "column_name" FROM "table_name" WHERE "simple condition" {[AND|OR] "simple condition"};
In
SELECT "column_name" FROM "table_name" WHERE "column_name" IN ('value1', 'value2', ...);
Between
SELECT "column_name" FROM "table_name" WHERE "column_name" BETWEEN 'value1' AND 'value2';
Like
SELECT "column_name" FROM "table_name" WHERE "column_name" LIKE {PATTERN};
Order By
SELECT "column_name" FROM "table_name" [WHERE "condition"] ORDER BY "column_name" [ASC, DESC];
Count
SELECT COUNT("column_name") FROM "table_name";
Group By
SELECT "column_name1", SUM("column_name2") FROM "table_name" GROUP BY "column_name1";
Having
SELECT "column_name1", [Function("column_name2")] FROM "table_name" [GROUP BY "column_name1"] HAVING (arithematic function condition);
Create Table Statement
CREATE TABLE "table_name" ("column 1" "data type for column 1" [column 1 constraint(s)], "column 2" "data type for column 2" [column 2 constraint(s)], ... [table constraint(s)]);
Drop Table Statement
DROP TABLE "table_name";
Truncate Table Statement
TRUNCATE TABLE "table_name";
Insert Into Statement
INSERT INTO "table_name" ("column1", "column2", ...) VALUES ("value1", "value2", ...);
Insert Into Select Statement
INSERT INTO "table1" ("column1", "column2", ...) SELECT "column3", "column4", ... FROM "table2";
Update Statement
UPDATE "table_name" SET "column_1" = [new value] WHERE "condition";
Delete From Statement
DELETE FROM "table_name" WHERE "condition";
SQL Syntax Checker
When we are writing complex SQL queries, there is a possibility of errors. That’s why Some SQL Syntax Checker tools or software are available online, which help check the syntax of SQL statements for errors and inconsistencies.
By using these SQL Syntax Checker tools, we can increase our productivity because these SQL Syntax Checker tools work by analyzing the structure and grammar of the SQL statements and comparing them to the rules and guidelines of the SQL language. Also, they can check things like missing keywords, incorrect use of clauses, and other syntax errors that could cause the SQL statement to fail.
That’s why most organizations nowadays are using SQL syntax checkers. Because with the help of these tools, they can save developers time and effort by identifying and correcting errors before the SQL statements are executed against a production database. This can help prevent data loss or corruption and improve the performance of the database by ensuring that the SQL statements are well-written and optimized.
Here are some of the SQL Syntax Checker Tools: EverSQL
Conclusion
This article will help you understand important concepts like SQL Syntax and SQL Syntax Checker tools. To know more about SQL, you can check our other SQL articles, and If you want to improve this article, you can share your inputs in the comment section.
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