Column name or number of supplied values does not match table definition

Emphasise explicit column naming

In your INSERT statement, explicitly mentioning column names can be as much of a lifesaver as the Ctrl+Z key. Not only does it evade confusion, but it's also an essential best practice dealing with tables having default values or computed columns:

-- INSERT with explicit columns: Like saying "This steak goes here, and the peas there."
INSERT INTO my_table (col1, col2, col3_with_default) VALUES ('value1', 'value2', DEFAULT);
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Specifying columns ensures that defaults are positioned correctly and only the intended columns are affected.

Steer clear of duplicate table names

Ambiguities make for great crime novels, not so much in your database schema. So, avoid duplicate table names! If you have tblTable1 and tblTable1_Link as names, consider:

• Dropping the old table after moving the data (Like the old toy, once the shiny new one's here, right?)
• Renaming tables to have clear, distinct labels (It's not just pets and babies who need unique names!)
• Using schemas to give the same-named tables a different lease of life.

Beware of the trigger menace

If your tables have any triggers altering data during INSERT operations, they might be your error's secret ingredient. So, be sure you're:

• Understanding and fixing trigger logic (It's just like taking a car apart and putting it back together, yes?)
• Turning off triggers temporarily for testing (Like pausing a movie to grab more popcorn)
• Validating all trigger operations to avoid unexpected plot twists during insertions.

Being friends with your schema

Consider your database schema as your favorite cookbook, and know it inside out. Recognize the columns that are computed, need explicit care during insertion, and remember the data types to ensure you're baking the right cakes — I mean, inserting the right values!

Safely migrating data between tables

When moving data between tables, especially from a linked server or database, ensure the columns align perfectly. For safe data migration, think of it as musical chairs:

-- INSERT data from one table to another with specific columns:
INSERT INTO my_table (col1, col2, col3)
SELECT col1, col2, col3 FROM another_table;
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Don't play the SELECT * card to avoid chaos when structure of both tables turns out different.

Dealing with temporary tables

For more complex scenarios dealing with data manipulation, you may want to insert values into temporary tables first to track down and debug issues:

-- Using a temporary table: Like drawing with a pencil before the final ink
DECLARE @TemporaryTable TABLE (col1 DataType1, col2 DataType2);
INSERT INTO @TemporaryTable (col1, col2) SELECT value1, value2 FROM source_table;
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This process helps to corner bugs before they raid your main tables.

Adaption to SQL Server syntax

Ensure your INSERT query syntax matches the SQL Server environment:

-- SQL Server friendly INSERT statement:
INSERT INTO my_table (column_list) VALUES (value_list);
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Who doesn't appreciate a well-mannered visitor, right? Ensure your scripts are the perfect guests, using SQL Server syntax.

Be cautious with INSERT INTO SELECT

When using INSERT INTO ... SELECT to move data, name your columns explicitly to avoid a nightmare scenario when the source and target tables are structurally distinct.

-- INSERT INTO SELECT with explicit column names:
INSERT INTO target_table (col1, col2)
SELECT col1, col2
FROM source_table;
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This strategy minimizes the risks of mismatches due to structural distinctions.