String Operators¶

Operators for working with string values.

Comparison Operators¶

Strings can be compared using standard comparison operators:

-- Equality
WHERE u.name = 'Alice'

-- Inequality
WHERE u.name <> 'Bob'

-- Less than (lexicographic)
WHERE u.name < 'Eve'

-- Greater than or equal
WHERE u.name >= 'Charlie'

String Matching Operators¶

Operator	Description	Example
`STARTS WITH`	String starts with prefix	`u.name STARTS WITH 'A'`
`ENDS WITH`	String ends with suffix	`u.email ENDS WITH '.com'`
`CONTAINS`	String contains substring	`u.name CONTAINS 'ana'`
`=~`	Regular expression match	`u.email =~ '.*@example\\.com'`

Examples¶

STARTS WITH¶

-- Find users whose name starts with 'A'
MATCH (u:User)
WHERE u.name STARTS WITH 'A'
RETURN u.name

-- Case-sensitive
WHERE u.name STARTS WITH 'alice'  -- Won't match 'Alice'

ENDS WITH¶

-- Find users with @example.com email
MATCH (u:User)
WHERE u.email ENDS WITH '@example.com'
RETURN u.name, u.email

-- Find .org domains
WHERE u.website ENDS WITH '.org'

CONTAINS¶

-- Search for substring
MATCH (u:User)
WHERE u.bio CONTAINS 'developer'
RETURN u.name

-- Multiple contains
WHERE u.bio CONTAINS 'developer' AND u.bio CONTAINS 'rust'

Regular Expression¶

-- Match email pattern
WHERE u.email =~ '^[a-z0-9._%+-]+@[a-z0-9.-]+\\.[a-z]{2,}$'

-- Match phone number format
WHERE u.phone =~ '^\\d{3}-\\d{3}-\\d{4}$'

-- Case-insensitive (using flags)
WHERE u.name =~ '(?i)alice'

Combining Operators¶

-- Domain filtering
WHERE u.email ENDS WITH '.com' OR u.email ENDS WITH '.org'

-- Name search
WHERE u.name STARTS WITH 'A' AND u.name CONTAINS 'li'

String Concatenation¶

Use the + operator to concatenate strings:

-- Concatenate first and last name
RETURN u.first_name + ' ' + u.last_name AS full_name

-- Build email
RETURN u.username + '@example.com' AS email

Case Sensitivity¶

String operations are case-sensitive by default:

-- These are different
'Alice' <> 'alice'
'ALICE' <> 'Alice'

For case-insensitive comparison:

-- Convert to lowercase first
WHERE LOWER(u.name) = LOWER('Alice')

-- Or use regex with flag
WHERE u.name =~ '(?i)alice'

NULL Handling¶

String operators return NULL if any operand is NULL:

-- NULL STARTS WITH 'A' = NULL
-- NULL CONTAINS 'x' = NULL
WHERE u.email IS NOT NULL AND u.email ENDS WITH '.com'

Performance Considerations¶

Operator	Performance	Index Usage
`=`	O(1) with index	Uses hash index
`STARTS WITH`	O(n)	Can use B-tree index
`ENDS WITH`	O(n)	Full scan
`CONTAINS`	O(n)	Full scan
`=~`	O(n*m)	Full scan

For large datasets, consider: - Using = with indexes when possible - Full-text search for complex text queries - Normalizing data (lowercase) for case-insensitive search

Escape Sequions¶

In string literals, use backslash to escape:

-- Single quote in string
WHERE u.name = 'O\'Reilly'

-- Backslash
WHERE u.path = 'C:\\Users\\Alice'

-- Newline, tab
WHERE u.text = 'Line 1\nLine 2\tTabbed'