PHP MSSQL - Making Columns to Take NULL


PHP MSSQL - How To Make a Column Nullable?

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Based on the testing result from the previous tutorial you can find out that there is a big difference in the column definition when running CREATE TABLE statement with mssql_query():

  • If CREATE TABLE is executed through mssql_query() and "NULL/NOT NULL" keyword is omitted in column definition, mssql_query() will assume NOT NULL.
  • If CREATE TABLE is executed directly on SQL Server and "NULL/NOT NULL" keyword is omitted in column definition, SQL Server will use NULL as the default.

Now you have to modify the CREATE TABLE statement to create "fyi_links" again by adding NULL to columns: notes, counts, and time:

  $con = mssql_connect('LOCALHOST','sa','FYIcenter');
  mssql_select_db('FyiCenterData', $con);

  # dropping an existing table
  $sql = "DROP TABLE fyi_links";
  $res = mssql_query($sql,$con);
  print("Table fyi_links dropped.\n");

  # creating a new table
  $sql = "CREATE TABLE fyi_links ("
      . " id INT NOT NULL" 
      . ", url VARCHAR(80) NOT NULL"
      . ", notes VARCHAR(1024) NULL"
      . ", counts INT NULL"
      . ", time DATETIME NULL"
      . ")";
  $res = mssql_query($sql,$con);
  print("Table fyi_links created.\n");


If you run this script, "fyi_links" will be dropped and created again with correct column definitions:

Table fyi_links dropped.
Table fyi_links created.


PHP MSSQL - Inserting Data with NULL Values

PHP MSSQL - Inserting Data into an Existing Table

SQL Server FAQs - PHP MSSQL Functions - Managing Tables and Data Rows

⇑⇑ SQL Server Connection Tutorials

2024-03-07, 1243🔥, 0💬