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HomeDatabaseSQLThe difference between like and = in sql

LIKE and = are operators used for string comparison in SQL. The main difference is that LIKE allows wildcard fuzzy matching (% and _), while = only works for exact matches. LIKE is suitable for fuzzy queries, has slower performance, and cannot use indexes. = is used for exact matching, faster performance, and indexing can be used. The choice of operator depends on the specific matching requirements of the query.

The difference between like and = in sql

The difference between LIKE and = in SQL

Clear the difference:

LIKE and = are the two major operators used to compare strings in SQL. The main difference is that LIKE allows wildcard characters (% and _), while = can only match the exact same string.

Detailed answer:

LIKE

  • ##Wildcard:

      %: Matches any number of characters (including 0)
    • _: Matches a single character
  • Syntax: FIELD LIKE 'PATTERN'
  • Usage: Widely used for fuzzy queries, such as finding strings that start or end with specific characters.

=

  • Exact match:

      Only matches the specified Strings with exactly the same value
  • Syntax: FIELD = 'VALUE'
  • Usage: Used for exact matching, such as finding specific records with specific values.

Example:

  • LIKE:

    • SELECT * FROM customers WHERE name LIKE '%Smith'
    • Find all customers whose last name ends with "Smith".
  • =:

    • SELECT * FROM orders WHERE order_id = 12345
    • Find the order with order ID 12345.

Other differences:

  • Performance: LIKE queries are generally slower than = queries because They involve fuzzy matching, requiring more complex comparisons to be performed.
  • Index: LIKE queries generally cannot use index optimization, while = queries can.
  • NULL values: LIKE returns NULL when comparing NULL values, while = returns FALSE.

Choose:

Select LIKE or = depending on the specific requirements of the query:

  • Use LIKE:

      When fuzzy matching is required.
  • Use =:

      When an exact match is required and performance and indexability are a priority factor.

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