Channel-retaining device, drainage system and method

A channel-retaining device (200), comprising:

• a retaining holder (102) which has a first coupling region (102k) and a retaining region (102a) for retaining a drainage channel extending along a direction;
• a retaining socket (104) which has a second coupling region (104k) and comprises a linkage;
• wherein the first coupling region (102k) and the second coupling region (104k) are configured to be joined together to form a joint (106) which provides the retaining holder (102) and the retaining socket (104) with one rotational degree of freedom (111) relative to one another which is essentially along the direction;
• a locking device (108) which is configured to be placed in a first state to block the rotational degree of freedom (111), so that the retaining holder (102) and the retaining socket (104) are locked together, and which is configured to be placed in a second state to release the rotational degree of freedom (111), so that the retaining holder (102) and the retaining socket (104) are movable relative to one another,
• wherein the linkage is articulated when the locking device (108) is in the second state and locked when the locking device (108) is in the first state.