search
HomeDatabaseSQLHow to enter data after sql creates table

After sql creates a table, you can use the ALTER TABLE statement to input data. The ALTER TABLE statement is used to add, delete, or modify columns in an existing table. If you need to add columns to the table, you can use the syntax "ALTER TABLE table_name ADD column_name...".

How to enter data after sql creates table

#The operating environment of this article: Windows 7 system, SQL Server 2016, Dell G3 computer.

After sql creates a table, you can use the ALTER TABLE statement to input data. The ALTER TABLE statement is used to add, delete, or modify columns in an existing table.

If you need to add a column to the table, please use the following syntax:

ALTER TABLE table_name
ADD column_name datatype

If you need to delete a column in the table, please use the following syntax (please note that some database systems do not allow This way of deleting a column in a database table):

ALTER TABLE table_name
DROP COLUMN column_name

Example:

Add a column named "DateOfBirth" to the "Persons" table.

ALTER TABLE Persons
ADD DateOfBirth date

Related recommendations: "SQL Tutorial"

The above is the detailed content of How to enter data after sql creates table. For more information, please follow other related articles on the PHP Chinese website!

Statement
The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn
OLTP vs OLAP: What about big data?OLTP vs OLAP: What about big data?May 14, 2025 am 12:06 AM

OLTPandOLAParebothessentialforbigdata:OLTPhandlesreal-timetransactions,whileOLAPanalyzeslargedatasets.1)OLTPrequiresscalingwithtechnologieslikeNoSQLforbigdata,facingchallengesinconsistencyandsharding.2)OLAPusesHadoopandSparktoprocessbigdata,withsetup

What is Pattern Matching in SQL and How Does It Work?What is Pattern Matching in SQL and How Does It Work?May 13, 2025 pm 04:09 PM

PatternmatchinginSQLusestheLIKEoperatorandregularexpressionstosearchfortextpatterns.Itenablesflexibledataqueryingwithwildcardslike%and_,andregexforcomplexmatches.It'sversatilebutrequirescarefulusetoavoidperformanceissuesandoveruse.

Learning SQL: Understanding the Challenges and RewardsLearning SQL: Understanding the Challenges and RewardsMay 11, 2025 am 12:16 AM

Learning SQL requires mastering basic knowledge, core queries, complex JOIN operations and performance optimization. 1. Understand basic concepts such as tables, rows, and columns and different SQL dialects. 2. Proficient in using SELECT statements for querying. 3. Master the JOIN operation to obtain data from multiple tables. 4. Optimize query performance, avoid common errors, and use index and EXPLAIN commands.

SQL: Unveiling Its Purpose and FunctionalitySQL: Unveiling Its Purpose and FunctionalityMay 10, 2025 am 12:20 AM

The core concepts of SQL include CRUD operations, query optimization and performance improvement. 1) SQL is used to manage and operate relational databases and supports CRUD operations. 2) Query optimization involves the parsing, optimization and execution stages. 3) Performance improvement can be achieved through the use of indexes, avoiding SELECT*, selecting the appropriate JOIN type and pagination query.

SQL Security Best Practices: Protecting Your Database from VulnerabilitiesSQL Security Best Practices: Protecting Your Database from VulnerabilitiesMay 09, 2025 am 12:23 AM

Best practices to prevent SQL injection include: 1) using parameterized queries, 2) input validation, 3) minimum permission principle, and 4) using ORM framework. Through these methods, the database can be effectively protected from SQL injection and other security threats.

MySQL: A Practical Application of SQLMySQL: A Practical Application of SQLMay 08, 2025 am 12:12 AM

MySQL is popular because of its excellent performance and ease of use and maintenance. 1. Create database and tables: Use the CREATEDATABASE and CREATETABLE commands. 2. Insert and query data: operate data through INSERTINTO and SELECT statements. 3. Optimize query: Use indexes and EXPLAIN statements to improve performance.

Comparing SQL and MySQL: Syntax and FeaturesComparing SQL and MySQL: Syntax and FeaturesMay 07, 2025 am 12:11 AM

The difference and connection between SQL and MySQL are as follows: 1.SQL is a standard language used to manage relational databases, and MySQL is a database management system based on SQL. 2.SQL provides basic CRUD operations, and MySQL adds stored procedures, triggers and other functions on this basis. 3. SQL syntax standardization, MySQL has been improved in some places, such as LIMIT used to limit the number of returned rows. 4. In the usage example, the query syntax of SQL and MySQL is slightly different, and the JOIN and GROUPBY of MySQL are more intuitive. 5. Common errors include syntax errors and performance issues. MySQL's EXPLAIN command can be used for debugging and optimizing queries.

SQL: A Guide for Beginners - Is It Easy to Learn?SQL: A Guide for Beginners - Is It Easy to Learn?May 06, 2025 am 12:06 AM

SQLiseasytolearnforbeginnersduetoitsstraightforwardsyntaxandbasicoperations,butmasteringitinvolvescomplexconcepts.1)StartwithsimplequerieslikeSELECT,INSERT,UPDATE,DELETE.2)PracticeregularlyusingplatformslikeLeetCodeorSQLFiddle.3)Understanddatabasedes

See all articles

Hot AI Tools

Undresser.AI Undress

Undresser.AI Undress

AI-powered app for creating realistic nude photos

AI Clothes Remover

AI Clothes Remover

Online AI tool for removing clothes from photos.

Undress AI Tool

Undress AI Tool

Undress images for free

Clothoff.io

Clothoff.io

AI clothes remover

Video Face Swap

Video Face Swap

Swap faces in any video effortlessly with our completely free AI face swap tool!

Hot Article

Hot Tools

SublimeText3 Chinese version

SublimeText3 Chinese version

Chinese version, very easy to use

Notepad++7.3.1

Notepad++7.3.1

Easy-to-use and free code editor

SublimeText3 Linux new version

SublimeText3 Linux new version

SublimeText3 Linux latest version

MantisBT

MantisBT

Mantis is an easy-to-deploy web-based defect tracking tool designed to aid in product defect tracking. It requires PHP, MySQL and a web server. Check out our demo and hosting services.

SAP NetWeaver Server Adapter for Eclipse

SAP NetWeaver Server Adapter for Eclipse

Integrate Eclipse with SAP NetWeaver application server.