Why do we use SQL limitations? Which constraints can we use while making a database in SQL?

  • Why do we use SQL limitations? Which constraints can we use while making a database in SQL?

  • Please expand on your questions, you may get more answers, if these are questions on a test, google is your friend. 🙂

  • agrawalanjita123 - Wednesday, January 16, 2019 5:05 AM

    Why do we use SQL limitations? Which constraints can we use while making a database in SQL?

    Try the following link... it will provide many links to answer those questions and teach you another skill that's super important in this business.
    http://bfy.tw/Lohb

    --Jeff Moden


    RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
    First step towards the paradigm shift of writing Set Based code:
    ________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
    "Change is inevitable... change for the better is not".

    Helpful Links:
    How to post code problems
    How to Post Performance Problems
    Create a Tally Function (fnTally)
    Intro to Tally Tables and Functions

  •  SQL Constraints are used to set the principles for all tables in the table. On the off chance that any imperatives get abused then it can prematurely end the activity that caused it.
    Constraints are characterized while making the database itself with CREATE TABLE explanation or even after the table is made once with ALTER TABLE statement.
    There are 5 noteworthy constraints we use as a part of SQL, for example,

    • NOT NULL: That demonstrates that the section must have some value and we can’t leave it invalid
    • Interesting:  We use this constraint to guarantee that each line and section has one of a kind value and we make sure we don’t rehash any values in some other line or segment
    • Essential KEY: We use this constraint as a part of the relationship with NOT NULL and UNIQUE imperatives, for example, on one or the mix of in excess of one segments to distinguish the specific record with a one of a kind character.
    • Remote KEY: Generally, we use it to guarantee the referential uprightness of data in the table and furthermore coordinates the incentive in one table with another utilizing Primary Key
    • CHECK:  We use it to guarantee whether the incentive in sections satisfies the predetermined condition.
  • agrawalanjita123 - Wednesday, January 16, 2019 5:05 AM

    Why do we use SQL limitations? Which constraints can we use while making a database in SQL?

    At the core of it all, to ensure that the data is as clean and accurate as possible.

    As to the list of constraints, that's what the documentation is for.

    ----------------------------------------------------
    The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood...
    Theodore Roosevelt

    The Scary DBA
    Author of: SQL Server 2017 Query Performance Tuning, 5th Edition and SQL Server Execution Plans, 3rd Edition
    Product Evangelist for Red Gate Software

  • rinu.gour123 - Wednesday, January 16, 2019 11:55 PM

     SQL Constraints are used to set the principles for all tables in the table. On the off chance that any imperatives get abused then it can prematurely end the activity that caused it.
    Constraints are characterized while making the database itself with CREATE TABLE explanation or even after the table is made once with ALTER TABLE statement.
    There are 5 noteworthy constraints we use as a part of SQL, for example,

    • NOT NULL: That demonstrates that the section must have some value and we can’t leave it invalid
    • Interesting:  We use this constraint to guarantee that each line and section has one of a kind value and we make sure we don’t rehash any values in some other line or segment
    • Essential KEY: We use this constraint as a part of the relationship with NOT NULL and UNIQUE imperatives, for example, on one or the mix of in excess of one segments to distinguish the specific record with a one of a kind character.
    • Remote KEY: Generally, we use it to guarantee the referential uprightness of data in the table and furthermore coordinates the incentive in one table with another utilizing Primary Key
    • CHECK:  We use it to guarantee whether the incentive in sections satisfies the predetermined condition.

    Obviously English isn't your primary language.  The constraints are NOT NULL, UNIQUE, PRIMARY KEY, FOREIGN KEY, and CHECK.

    Drew

    J. Drew Allen
    Business Intelligence Analyst
    Philadelphia, PA

  • drew.allen - Thursday, January 17, 2019 9:57 AM

    rinu.gour123 - Wednesday, January 16, 2019 11:55 PM

     SQL Constraints are used to set the principles for all tables in the table. On the off chance that any imperatives get abused then it can prematurely end the activity that caused it.
    Constraints are characterized while making the database itself with CREATE TABLE explanation or even after the table is made once with ALTER TABLE statement.
    There are 5 noteworthy constraints we use as a part of SQL, for example,

    • NOT NULL: That demonstrates that the section must have some value and we can’t leave it invalid
    • Interesting:  We use this constraint to guarantee that each line and section has one of a kind value and we make sure we don’t rehash any values in some other line or segment
    • Essential KEY: We use this constraint as a part of the relationship with NOT NULL and UNIQUE imperatives, for example, on one or the mix of in excess of one segments to distinguish the specific record with a one of a kind character.
    • Remote KEY: Generally, we use it to guarantee the referential uprightness of data in the table and furthermore coordinates the incentive in one table with another utilizing Primary Key
    • CHECK:  We use it to guarantee whether the incentive in sections satisfies the predetermined condition.

    Obviously English isn't your primary language.  The constraints are NOT NULL, UNIQUE, PRIMARY KEY, FOREIGN KEY, and CHECK.

    Drew

    More likely, that's copied from a blog post that was stolen. I've seen my posts get stolen and some of the words get substituted so that the post looks unique. However, instead, you get something that is blatantly wrong, such as INTERESTING gets changed from UNIQUE. PRIMARY becomes Essential. Foreign becomes Remote.

    It's a double frustrating thing. The plagiarism bothers me, but then the rewriting of the material so that it's just utterly WRONG bothers me even more.

    ----------------------------------------------------
    The credit belongs to the man who is actually in the arena, whose face is marred by dust and sweat and blood...
    Theodore Roosevelt

    The Scary DBA
    Author of: SQL Server 2017 Query Performance Tuning, 5th Edition and SQL Server Execution Plans, 3rd Edition
    Product Evangelist for Red Gate Software

  • Grant Fritchey - Thursday, January 17, 2019 12:50 PM

    drew.allen - Thursday, January 17, 2019 9:57 AM

    rinu.gour123 - Wednesday, January 16, 2019 11:55 PM

     SQL Constraints are used to set the principles for all tables in the table. On the off chance that any imperatives get abused then it can prematurely end the activity that caused it.
    Constraints are characterized while making the database itself with CREATE TABLE explanation or even after the table is made once with ALTER TABLE statement.
    There are 5 noteworthy constraints we use as a part of SQL, for example,

    • NOT NULL: That demonstrates that the section must have some value and we can’t leave it invalid
    • Interesting:  We use this constraint to guarantee that each line and section has one of a kind value and we make sure we don’t rehash any values in some other line or segment
    • Essential KEY: We use this constraint as a part of the relationship with NOT NULL and UNIQUE imperatives, for example, on one or the mix of in excess of one segments to distinguish the specific record with a one of a kind character.
    • Remote KEY: Generally, we use it to guarantee the referential uprightness of data in the table and furthermore coordinates the incentive in one table with another utilizing Primary Key
    • CHECK:  We use it to guarantee whether the incentive in sections satisfies the predetermined condition.

    Obviously English isn't your primary language.  The constraints are NOT NULL, UNIQUE, PRIMARY KEY, FOREIGN KEY, and CHECK.

    Drew

    More likely, that's copied from a blog post that was stolen. I've seen my posts get stolen and some of the words get substituted so that the post looks unique. However, instead, you get something that is blatantly wrong, such as INTERESTING gets changed from UNIQUE. PRIMARY becomes Essential. Foreign becomes Remote.

    It's a double frustrating thing. The plagiarism bothers me, but then the rewriting of the material so that it's just utterly WRONG bothers me even more.

    That makes sense, especially when you look at the case irregularities.

    Drew

    J. Drew Allen
    Business Intelligence Analyst
    Philadelphia, PA

  • drew.allen - Thursday, January 17, 2019 1:15 PM

    Grant Fritchey - Thursday, January 17, 2019 12:50 PM

    drew.allen - Thursday, January 17, 2019 9:57 AM

    rinu.gour123 - Wednesday, January 16, 2019 11:55 PM

     SQL Constraints are used to set the principles for all tables in the table. On the off chance that any imperatives get abused then it can prematurely end the activity that caused it.
    Constraints are characterized while making the database itself with CREATE TABLE explanation or even after the table is made once with ALTER TABLE statement.
    There are 5 noteworthy constraints we use as a part of SQL, for example,

    • NOT NULL: That demonstrates that the section must have some value and we can’t leave it invalid
    • Interesting:  We use this constraint to guarantee that each line and section has one of a kind value and we make sure we don’t rehash any values in some other line or segment
    • Essential KEY: We use this constraint as a part of the relationship with NOT NULL and UNIQUE imperatives, for example, on one or the mix of in excess of one segments to distinguish the specific record with a one of a kind character.
    • Remote KEY: Generally, we use it to guarantee the referential uprightness of data in the table and furthermore coordinates the incentive in one table with another utilizing Primary Key
    • CHECK:  We use it to guarantee whether the incentive in sections satisfies the predetermined condition.

    Obviously English isn't your primary language.  The constraints are NOT NULL, UNIQUE, PRIMARY KEY, FOREIGN KEY, and CHECK.

    Drew

    More likely, that's copied from a blog post that was stolen. I've seen my posts get stolen and some of the words get substituted so that the post looks unique. However, instead, you get something that is blatantly wrong, such as INTERESTING gets changed from UNIQUE. PRIMARY becomes Essential. Foreign becomes Remote.

    It's a double frustrating thing. The plagiarism bothers me, but then the rewriting of the material so that it's just utterly WRONG bothers me even more.

    That makes sense, especially when you look at the case irregularities.

    Drew

    Too weird and not sure why they were posting all of this. The question AND the answer are verbatim from the same site - check out question 5 (question even worded the same):
    Top SQL Interview Questions and Answers – Crack Your Next Interview

    Sue

  • Sue_H - Thursday, January 17, 2019 4:01 PM

    drew.allen - Thursday, January 17, 2019 1:15 PM

    Grant Fritchey - Thursday, January 17, 2019 12:50 PM

    drew.allen - Thursday, January 17, 2019 9:57 AM

    rinu.gour123 - Wednesday, January 16, 2019 11:55 PM

     SQL Constraints are used to set the principles for all tables in the table. On the off chance that any imperatives get abused then it can prematurely end the activity that caused it.
    Constraints are characterized while making the database itself with CREATE TABLE explanation or even after the table is made once with ALTER TABLE statement.
    There are 5 noteworthy constraints we use as a part of SQL, for example,

    • NOT NULL: That demonstrates that the section must have some value and we can’t leave it invalid
    • Interesting:  We use this constraint to guarantee that each line and section has one of a kind value and we make sure we don’t rehash any values in some other line or segment
    • Essential KEY: We use this constraint as a part of the relationship with NOT NULL and UNIQUE imperatives, for example, on one or the mix of in excess of one segments to distinguish the specific record with a one of a kind character.
    • Remote KEY: Generally, we use it to guarantee the referential uprightness of data in the table and furthermore coordinates the incentive in one table with another utilizing Primary Key
    • CHECK:  We use it to guarantee whether the incentive in sections satisfies the predetermined condition.

    Obviously English isn't your primary language.  The constraints are NOT NULL, UNIQUE, PRIMARY KEY, FOREIGN KEY, and CHECK.

    Drew

    More likely, that's copied from a blog post that was stolen. I've seen my posts get stolen and some of the words get substituted so that the post looks unique. However, instead, you get something that is blatantly wrong, such as INTERESTING gets changed from UNIQUE. PRIMARY becomes Essential. Foreign becomes Remote.

    It's a double frustrating thing. The plagiarism bothers me, but then the rewriting of the material so that it's just utterly WRONG bothers me even more.

    That makes sense, especially when you look at the case irregularities.

    Drew

    Too weird and not sure why they were posting all of this. The question AND the answer are verbatim from the same site - check out question 5 (question even worded the same):
    Top SQL Interview Questions and Answers – Crack Your Next Interview

    Sue

    Heh... ah... the old spam advertising trick.  Someone from the company asks a question and then someone answers it and conveniently has a link in the answer right back to the original question and the answers and the business of offering tutorials to help you answer such questions. 

    To summarize, a con job to get us to click on their junk without the posts being flagged as spam... which all of this is.

    And, as Grant so very well observed, it isn't just junk... it's improperly translated stuff they stole from other websites.

    --Jeff Moden


    RBAR is pronounced "ree-bar" and is a "Modenism" for Row-By-Agonizing-Row.
    First step towards the paradigm shift of writing Set Based code:
    ________Stop thinking about what you want to do to a ROW... think, instead, of what you want to do to a COLUMN.
    "Change is inevitable... change for the better is not".

    Helpful Links:
    How to post code problems
    How to Post Performance Problems
    Create a Tally Function (fnTally)
    Intro to Tally Tables and Functions

  • Block the users !
    Spambots !

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